Parasiticidal compositions comprising an isoxazoline active agent, methods and uses thereof

ABSTRACT

This invention relates to topical compositions for combating ectoparasites and endoparasites in animals, comprising at least one isoxazoline active agent and a pharmaceutically acceptable carrier, optionally in combination with one or more additional active agents. This invention also provides for an improved methods for eradicating, controlling, and preventing parasite infections and infestations in an animal comprising administering the compositions of the invention to the animal in need thereof.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to U.S. ProvisionalApplication No. 61/533,308 filed Sep. 12, 2011, which is incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present invention provides topical veterinary compositionscomprising at least one isoxazoline active agent for controllingectoparasites and endoparasites in animals; the use of thesecompositions against ectoparasites and/or endoparasites, and methods forpreventing or treating parasitic infections and infestations in animals.

BACKGROUND OF THE INVENTION

Animals such as mammals and birds are often susceptible to parasiteinfestations/infections. These parasites may be ectoparasites, such asinsects, and endoparasites such as filariae and other worms.Domesticated animals, such as cats and dogs, are often infested with oneor more of the following ectoparasites:

-   -   fleas (e.g. Ctenocephalides spp., such as Ctenocephalides felis        and the like);    -   ticks (e.g. Rhipicephalus spp., Ixodes spp., Dermacentor spp.,        Amblyoma spp., and the like);    -   mites (e.g. Demodex spp., Sarcoptes spp., Otodectes spp., and        the like);    -   lice (e.g. Trichodectes spp., Cheyletiella spp., Lignonathus        spp. and the like);    -   mosquitoes (Aedes spp., Culux spp., Anopheles spp. and the        like); and    -   flies (Hematobia spp., Musca spp., Stomoxys spp., Dematobia        spp., Coclyomia spp. and the like).

Fleas are a particular problem because not only do they adversely affectthe health of the animal or human, but they also cause a great deal ofpsychological stress. Moreover, fleas are also vectors of pathogenicagents in animals and humans, such as dog tapeworm (Dipylidium caninum).

Similarly, ticks are also harmful to the physical and psychologicalhealth of the animal or human. However, the most serious problemassociated with ticks is that they are the vector of pathogenic agentsin both humans and animals. Major diseases which are caused by ticksinclude borrelioses (Lyme disease caused by Borrelia burgdorferi),babesioses (or piroplasmoses caused by Babesia spp.) and rickettsioses(also known as Rocky Mountain spotted fever). Ticks also release toxinswhich cause inflammation or paralysis in the host. Occasionally, thesetoxins are fatal to the host.

Likewise, farm animals are also susceptible to parasite infestations.For example, cattle are affected by a large number of parasites. Aparasite which is very prevalent among farm animals is the tick genusRhipicephalus, especially those of the species microplus (cattle tick),decoloratus and annulatus. Ticks such as Rhipicephalus microplus(formerly Boophilus microplus) are particularly difficult to controlbecause they live in the pasture where farm animals graze. This speciesof ticks is considered a one-host tick and spends immature and adultstages on one animal before the female engorges and falls off the hostto lay eggs in the environment. The life cycle of the tick isapproximately three to four weeks. In addition to cattle, Rhipicephalusmicroplus may infest found on buffalo, horses, donkeys, goats, sheep,deer, pigs, and dogs. A heavy tick burden on animals can decreaseproduction and damage hides as well as transmit diseases such asbabesiosis (“cattle fever”) and anaplasmosis caused by protozoanparasites.

Animals and humans also suffer from endoparasitic infections including,for example, helminthiasis which is most frequently caused by a group ofparasitic worms categorized as cestodes (tapeworm), nematodes(roundworm) and trematodes (flatworm or flukes). These parasitesadversely affect the nutrition of the animal and cause severe economiclosses in pigs, sheep, horses, and cattle as well as affecting domesticanimals and poultry. Other parasites which occur in the gastrointestinaltract of animals and humans include Ancylostoma, Necator, Ascaris,Strongyloides, Trichinella, Capillaria, Toxocara, Toxascaris, Trichiris,Enterobius and parasites which are found in the blood or other tissuesand organs such as filarial worms and the extra intestinal stages ofStrogyloides, Toxocara and Trichinella.

Recently, isoxazole and isoxazoline-containing compounds have beendemonstrated to be effective against parasites that harm animals. Forexample, US 2010/0234219 A1 (to DuPont) discloses isoxazoline compoundsaccording to Formula (I) below, which are active against ectoparasitesand/or endoparasites.

In addition, published patent application nos. US 2010/0254960 A1, WO2007/070606 A2, WO 2007/123855 A2, WO 2010/003923 A1, U.S. Pat. No.7,951,828 & U.S. Pat. No. 7,662,972, US 2010/0137372 A1, US 2010/0179194A2, US 2011/0086886 A2, US 2011/0059988 A1, US 2010/0179195 A1 and WO2007/075459 A2 and U.S. Pat. Nos. 7,951,828 and 7,662,972 describevarious other parasiticidal isoxazoline compounds. WO 2012/089623describes topical localized isoxazoline formulations comprisingglycofurol.

Notwithstanding the compositions comprising isoxazoline active agentsalone or in combination with other active agents described in thedocuments above, there is a need for veterinary compositions and methodswith improved efficacy, bioavailability, and spectrum of coverage toprotect animals against endoparasites and/or ectoparasites. Optimalcompositions should provide contact and/or systemic activity, beefficacious, have a quick onset of activity, have a long duration ofactivity, and be safe to the animal recipient and their human owners.This invention addresses this need.

INCORPORATION BY REFERENCE

Any foregoing applications, and all documents cited therein or duringtheir prosecution (“application cited documents”) and all documentscited or referenced in the application cited documents, and alldocuments cited or referenced herein (“herein cited documents”), and alldocuments cited or referenced in herein cited documents, together withany manufacturer's instructions, descriptions, product specifications,and product sheets for any products mentioned herein or in any documentincorporated by reference herein, are hereby incorporated herein byreference, and may be employed in the practice of the invention.

Citation or identification of any document in this application is not anadmission that such document is available as prior art to the presentinvention.

SUMMARY OF THE INVENTION

The present invention is directed to topical compositions comprising atleast one isoxazoline, alone or in combination with other active agents,and their use to control parasites in or on warm-blooded animals andbirds. In accordance with this invention, it has been discovered thatthese compositions generally show desirable bioavailability, and canprovide contact and/or systemic activity. The compositions also providedesirable safety profiles toward the warm-blooded and bird animalrecipients. In addition, it has been discovered that a singleadministration of such compositions generally provides potent activityagainst one or more ectoparasites, while also tending to provide fastonset of activity, long duration of activity, and/or desirable safetyprofiles.

The invention encompasses uses or veterinary uses of the isoxazolinecompositions for the treatment or prophylaxis of parasitic infectionsand infestations of animals (either wild or domesticated), includinglivestock and companion animals such as cats, dogs, horses, chickens,sheep, goats, pigs, turkeys and cattle, with the aim of ridding thesehosts of parasites commonly encountered by such animals.

In a particularly preferred embodiment, the composition is a topicalspot-on formulation. In another preferred embodiment particularly wellsuited for livestock animals, the composition is a topical pour-onformulation. The invention also includes other topical compositionscomprising an isoxazoline active agent including sprays, aerosols, foamsand the like.

In some embodiments, the topical veterinary composition comprises apharmaceutically acceptable carrier wherein the carrier comprises adiester of a dicarboxylic acid, a glycol ester, a glycol ether, a fattyacid ester, a polyethylene glycol, or polyethylene glycol ester, an oil,an alcohol, a glycerol ester, a glycerol ether, propylene glycol,ethylene glycol, a glycol carbonate, dimethyl isosorbide,N-methylpyrrolidone, or a mixture thereof.

In one embodiment, the diester of a dicarboxylic acid is a diester of aC₆-C₁₆ dicarboxylic acid including, but not limited to, diethyl sebacateor diisopropyl adipate.

In another embodiment of the invention, the pharmaceutically acceptablecarrier of the compositions comprises mixture of a diester of adicarboxylic acid and a propylene glycol ester, a fatty acid ester, apolyethylene glycol ester, a polyethylene glycol, an oil, a C₆-C₂₀long-chain aliphatic alcohol, a C₁-C₈ alcohol, glycol ether, or acombination thereof.

In certain embodiments, the pharmaceutically acceptable carrier of thetopical veterinary composition of the invention further comprises amixed ester of sucrose and acetic and isobutyric acid, a low meltingwax, a hard fat or a block co-polymer of ethylene oxide and propyleneoxide, or a combination thereof.

In another embodiment, the pharmaceutically acceptable carrier comprisesdimethyl isosorbide, glycerol formal, propylene carbonate, triacetin,diethyleneglycol monoethyl ether, polyethylene glycol 400 or benzylalcohol, or a mixture thereof.

The invention also provides methods for the treatment or prevention ofparasitic infections and infestations in animals, comprisingadministering an effective amount of a composition comprising at leastone isoxazoline to the animal. Surprisingly, it has been found that theinventive compositions and formulations described herein exhibitsuperior broad spectrum efficacy against harmful ectoparasites morerapidly, and over a long duration compared to compositions known in theart.

In one embodiment, the invention provides topical veterinarycompositions comprising effective amounts of at least one isoxazoline offormula (I) below, in combination and a pharmaceutically or veterinarilyacceptable liquid carrier, where variables A¹, A², A³, A⁴, A⁵, A⁶, B¹,B², B³, R¹, R², R³, R⁴, R⁵, W are defined herein.

In some embodiments, the topical veterinary compositions and methodscomprise4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalenecarboxamideas the active agent.

In other embodiments, the compositions may further comprise one or moreadditional active agents. In one embodiment, the compositions compriseat least one macrocyclic lactone active agent, including, but notlimited to, avermectins or milbemycins. In some embodiments, theavermectin or milbemycin active agent is eprinomectin, ivermectin,selamectin, milbemectin, milbemycin D, milbemycin oxime, or moxidectin.

In another embodiment, the topical compositions of the invention includea combination of an isoxazoline active agent with the neonicotinoidactive agent nitenpyram.

In other embodiments, the compositions and methods of the invention mayfurther comprise an insect growth regulator (IGR) active agent,including but not limited to, methoprene, pyriproxyfen, hydroprene,cyromazine, fluazuron, lufenuron, or novaluron. In another preferredembodiment, the compositions of the invention comprise a neonicotinoidactive agent such as nitenpyram. In other embodiments, the compositionsand methods comprise at least one of thiabendazole, oxibendazole,mebendazole, fenbendazole, oxfendazole, albendazole, triclabendazole,febantel, levamisole, pyrantel, morantel, praziquantel, closantel,clorsulon, an amino acetonitrile active agent, or an aryloazol-2-ylcyanoethylamino active agent.

It is an object of the invention to not encompass within the inventionany previously known product, process of making the product, or methodof using the product such that the Applicants reserve the right andhereby disclose a disclaimer of any previously known product, process,or method. It is further noted that the invention does not intend toencompass within the scope of the invention any product, process, ormaking of the product or method of using the product, which does notmeet the written description and enablement requirements of the USPTO(35 U.S.C. §112, first paragraph) or the EPO (Article 83 of the EPC),such that Applicants reserve the right and hereby disclose a disclaimerof any previously described product, process of making the product, ormethod of using the product.

These and other embodiments are disclosed or are obvious from andencompassed by, the following Detailed Description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plot showing the long lasting efficacy of a spot-oncomposition comprising Compound A against Ctenocephalides felis fleas incats (Example 9).

FIG. 2 is a plot showing the long lasting efficacy of a pour-oncomposition comprising Compound A against Rhipicephalus (Boophilus)microplus in cattle based on the number of ticks dropped (Example 15).

FIG. 3 is a plot showing the long lasting efficacy of a pour-oncomposition comprising Compound A against Rhipicephalus (Boophilus)microplus in cattle based on the weight of ticks that drop (Example 15).

DETAILED DESCRIPTION

The present invention provides novel and inventive topical compositionscomprising at least one isoxazoline compound together with apharmaceutically acceptable carrier or diluent that is suitable fortopical application to an animal.

In some embodiments of the invention, the compositions preferablyinclude spot-on or pour-on formulations that are applied to a localizedarea on an animal. Topical spray, aerosol or foam formulations, whichtypically include the active agent in lower concentrations, are alsoencompassed by the invention. These formulations provide surprisinglyeffective protection of the animals against parasites for an extendedperiod of time. The formulations also provide extremely rapid killing ofparasites infesting animals.

Also provided are methods and uses for the treatment and/or prophylaxisof parasitic infections and infestations of animals, comprisingadministering an effective amount of a formulation of the invention tothe animal.

The invention includes at least the following features:

(a) topical veterinary formulations that exhibit superior activityagainst animal parasites comprising at least one isoxazoline activeagent together with a pharmaceutically acceptable carrier or diluentthat is suitable for topical application to an animal;

(b) topical veterinary compositions that exhibit superior long lastingefficacy that comprise at least one isoxazoline compound of formula (I)described herein together with a pharmaceutically acceptable carrier ordiluent that is suitable for topical application to an animal;

(c) topical veterinary compositions that exhibit superior long lastingefficacy that comprise at least one isoxazoline active agent incombination with one or more other active agents together with apharmaceutically acceptable carrier or diluent that is suitable fortopical application to an animal;

(d) topical veterinary compositions comprising an effective amount of anisoxazoline active agent together with a pharmaceutically acceptablecarrier or diluent that is suitable for topical application to ananimal, wherein the carrier does not comprise glycofurol;

(e) topical veterinary compositions comprising an effective amount of anisoxazoline active agent together with a pharmaceutically acceptablecarrier or diluent that is suitable for topical application to ananimal, wherein the carrier is not a binary mixture of propylene glycoland glycerol formal;

(f) methods for the treatment or prevention of parasitic infections andinfestations in an animal comprising administering an effective amountof a composition comprising at least one isoxazoline active agenttogether with a pharmaceutically acceptable carrier or diluent;

(g) methods for the treatment or prevention of parasitic infections andinfestations in an animal comprising administering an effective amountof a composition comprising at least one isoxazoline active agent with apharmaceutically acceptable carrier or diluent that is suitable fortopical application to an animal;

(h) methods for the treatment or prevention of parasitic infections andinfestations in an animal comprising administering an effective amountof a topical composition comprising at least one isoxazoline activeagent in combination with one or more other active agents together witha pharmaceutically acceptable carrier or diluent that is suitable fortopical application to an animal;

(i) use of veterinary compositions comprising at least one isoxazolinecompound, including a compound of formula (I), together with apharmaceutically acceptable carrier or diluent in the prevention ortreatment of animal parasites.

In this disclosure and in the claims, terms such as “comprises,”“comprising,” “containing” and “having” and the like can have themeaning ascribed to them in U.S. Patent law and can mean “includes,”“including,” and the like; “consisting essentially of” or “consistsessentially” likewise has the meaning ascribed in U.S. Patent law andthe term is open-ended, allowing for the presence of more than thatwhich is recited so long as basic or novel characteristics of that whichis recited is not changed by the presence of more than that which isrecited, but excludes prior art embodiments.

DEFINITIONS

Terms used herein will have their customary meaning in the art unlessspecified otherwise. The organic moieties mentioned in the definitionsof the variables of formula (I) are—like the term halogen—collectiveterms for individual listings of the individual group members. Theprefix C_(n)-C_(m) indicates in each case the possible number of carbonatoms in the group.

The term “animal” is used herein to include all mammals, birds and fishand also include all vertebrate animals. Animals include, but are notlimited to, cats, dogs, cattle, chickens, cows, deer, goats, horses,llamas, pigs, sheep and yaks. It also includes an individual animal inall stages of development, including embryonic and fetal stages. In someembodiments, the animal will be a non-human animal.

The term “fatty acid” refers to carboxylic acids having from 4 to 26carbon atoms.

The terms “fatty alcohol” or “long-chain aliphatic alcohol” refer toaliphatic alcohols containing from 6 to 20 carbon atoms.

The term “low melting” refers to substances that are solids at roomtemperature but melt into liquids below 50° C.

The term “alkyl” refers to saturated straight, branched, cyclic,primary, secondary or tertiary hydrocarbons, including those having 1 to20 atoms. In some embodiments, alkyl groups will include C₁-C₁₂, C₁-C₁₀,C₁-C₈, C₁-C₆ or C₁-C₄ alkyl groups. Examples of C₁-C₁₀ alkyl include,but are not limited to, methyl, ethyl, propyl, 1-methylethyl, butyl,1-methylpropyl, 2-methylpropyl, 1,1-dimethylethyl, pentyl,1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl,1-ethylpropyl, hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl,1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl,1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl,2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl,1-ethyl-1-methylpropyl, 1-ethyl-2-methylpropyl, heptyl, octyl,2-ethylhexyl, nonyl and decyl and their isomers. C₁-C₄-alkyl means forexample methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl,2-methylpropyl or 1,1-dimethylethyl.

Cyclic alkyl groups or “cycloalkyl”, which are encompassed by alkylinclude those with 3 to 10 carbon atoms having single or multiplecondensed rings. In some embodiments, cycloalkyl groups include C₄-C₇ orC₃-C₄ cyclic alkyl groups. Non-limiting examples of cycloalkyl groupsinclude adamantyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl, cyclooctyl and the like.

The alkyl groups described herein can be unsubstituted or substitutedwith one or more moieties selected from the group consisting of alkyl,halo, haloalkyl, hydroxyl, carboxyl, acyl, acyloxy, amino, alkyl- ordialkylamino, amido, arylamino, alkoxy, aryloxy, nitro, cyano, azido,thiol, imino, sulfonic acid, sulfate, sulfonyl, sulfanyl, sulfinyl,sulfamoyl, ester, phosphonyl, phosphinyl, phosphoryl, phosphine,thioester, thioether, acid halide, anhydride, oxime, hydrazine,carbamate, phosphoric acid, phosphate, phosphonate, or any other viablefunctional group that does not inhibit the biological activity of thecompounds of the invention, either unprotected, or protected asnecessary, as known to those skilled in the art, for example, as taughtin Greene, et al., Protective Groups in Organic Synthesis, John Wileyand Sons, Third Edition, 1999, hereby incorporated by reference.

Terms including the term “alkyl” such as “alkylcycloalkyl,”“cycloalkylalkyl,” “alkylamino,” or “dialkylamino” will be understood tocomprise an alkyl group as defined above linked to the other functionalgroup, where the group is linked to the compound through the last grouplisted, as understood by those of skill in the art.

The term “alkenyl” refers to both straight and branched carbon chainswhich have at least one carbon-carbon double bond. In some embodiments,alkenyl groups may include C₂-C₂₀ alkenyl groups. In other embodiments,alkenyl includes C₂-C₁₂, C₂-C₁₀, C₂-C₈, C₂-C₆ or C₂-C₄ alkenyl groups.In one embodiment of alkenyl, the number of double bonds is 1-3, inanother embodiment of alkenyl, the number of double bonds is one or two.Other ranges of carbon-carbon double bonds and carbon numbers are alsocontemplated depending on the location of the alkenyl moiety on themolecule. “C₂-C₁₀-alkenyl” groups may include more than one double bondin the chain. Examples include, but are not limited to, ethenyl,1-propenyl, 2-propenyl, 1-methyl-ethenyl, 1-butenyl, 2-butenyl,3-butenyl, 1-methyl-1-propenyl, 2-methyl-1-propenyl,1-methyl-2-propenyl, 2-methyl-2-propenyl; 1-pentenyl, 2-pentenyl,3-pentenyl, 4-pentenyl, 1-methyl-1-butenyl, 2-methyl-1-butenyl,3-methyl-1-butenyl, 1-methyl-2-butenyl, 2-methyl-2-butenyl,3-methyl-2-butenyl, 1-methyl-3-butenyl, 2-methyl-3-butenyl,3-methyl-3-butenyl, 1,1-dimethyl-2-propenyl, 1,2-dimethyl-1-propenyl,1,2-dimethyl-2-propenyl, 1-ethyl-1-propenyl, 1-ethyl-2-propenyl,1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl,1-methyl-1-pentenyl, 2-methyl-1-pentenyl, 3-methyl-1-pentenyl,4-methyl-1-pentenyl, 1-methyl-2-pentenyl, 2-methyl-2-pentenyl,3-methyl-2-pentenyl, 4-methyl-2-pentenyl, 1-methyl-3-pentenyl,2-methyl-3-pentenyl, 3-methyl-3-pentenyl, 4-methyl-3-pentenyl,1-methyl-4-pentenyl, 2-methyl-4-pentenyl, 3-methyl-4-pentenyl,4-methyl-4-pentenyl, 1,1-dimethyl-2-butenyl, 1,1-dimethyl-3-butenyl,1,2-dimethyl-1-butenyl, 1,2-dimethyl-2-butenyl, 1,2-dimethyl-3-butenyl,1,3-dimethyl-1-butenyl, 1,3-dimethyl-2-butenyl, 1,3-dimethyl-3-butenyl,2,2-dimethyl-3-butenyl, 2,3-dimethyl-1-butenyl, 2,3-dimethyl-2-butenyl,2,3-dimethyl-3-butenyl, 3,3-dimethyl-1-butenyl, 3,3-dimethyl-2-butenyl,1-ethyl-1-butenyl, 1-ethyl-2-butenyl, 1-ethyl-3-butenyl,2-ethyl-1-butenyl, 2-ethyl-2-butenyl, 2-ethyl-3-butenyl,1,1,2-trimethyl-2-propenyl, 1-ethyl-1-methyl-2-propenyl,1-ethyl-2-methyl-1-propenyl and 1-ethyl-2-methyl-2-propenyl.

“Alkynyl” refers to both straight and branched carbon chains which haveat least one carbon-carbon triple bond. In one embodiment of alkynyl,the number of triple bonds is 1-3; in another embodiment of alkynyl, thenumber of triple bonds is one or two. In some embodiments, alkynylgroups include from C₂-C₂₀ alkynyl groups. In other embodiments, alkynylgroups may include C₂-C₁₂, C₂-C₁₀, C₂-C₈, C₂-C₆ or C₂-C₄ alkynyl groups.Other ranges of carbon-carbon triple bonds and carbon numbers are alsocontemplated depending on the location of the alkenyl moiety on themolecule. For example, the term “C₂-C₁₀-alkynyl” as used herein refersto a straight-chain or branched unsaturated hydrocarbon group having 2to 10 carbon atoms and containing at least one triple bond, such asethynyl, prop-1-yn-1-yl, prop-2-yn-1-yl, n-but-1-yn-1-yl,n-but-1-yn-3-yl, n-but-1-yn-4-yl, n-but-2-yn-1-yl, n-pent-1-yn-1-yl,n-pent-1-yn-3-yl, n-pent-1-yn-4-yl, n-pent-1-yn-5-yl, n-pent-2-yn-1-yl,n-pent-2-yn-4-yl, n-pent-2-yn-5-yl, 3-methylbut-1-yn-3-yl,3-methylbut-1-yn-4-yl, n-hex-1-yn-1-yl, n-hex-1-yn-3-yl,n-hex-1-yn-4-yl, n-hex-1-yn-5-yl, n-hex-1-yn-6-yl, n-hex-2-yn-1-yl,n-hex-2-yn-4-yl, n-hex-2-yn-5-yl, n-hex-2-yn-6-yl, n-hex-3-yn-1-yl,n-hex-3-yn-2-yl, 3-methylpent-1-yn-1-yl, 3-methylpent-1-yn-3-yl,3-methylpent-1-yn-4-yl, 3-methylpent-1-yn-5-yl, 4-methylpent-1-yn-1-yl,4-methylpent-2-yn-4-yl or 4-methylpent-2-yn-5-yl and the like.

The term “haloalkyl” refers to an alkyl group, as defined herein, whichis substituted by one or more halogen atoms. For example C₁-C₄-haloalkylincludes, but is not limited to, chloromethyl, bromomethyl,dichloromethyl, trichloromethyl, fluoromethyl, difluoromethyl,trifluoromethyl, chlorofluoromethyl, dichlorofluoromethyl,chlorodifluoromethyl, 1-chloroethyl, 1-bromoethyl, 1-fluoroethyl,2-fluoroethyl, 2,2-difluoroethyl, 2,2,2-trifluoroethyl,2-chloro-2-fluoroethyl, 2-chloro-2,2-difluoroethyl,2,2-dichloro-2-fluoroethyl, 2,2,2-trichloroethyl, pentafluoroethyl andthe like.

The term “haloalkenyl” refers to an alkenyl group, as defined herein,which is substituted by one or more halogen atoms.

The term “haloalkynyl” refers to an alkynyl group, as defined herein,which is substituted by one or more halogen atoms.

“Alkoxy” refers to alkyl-O—, wherein alkyl is as defined above.Similarly, the terms “alkenyloxy,” “alkynyloxy,” “haloalkoxy,”“haloalkenyloxy,” “haloalkynyloxy,” “cycloalkoxy,” “cycloalkenyloxy,”“halocycloalkoxy,” and “halocycloalkenyloxy” refer to the groupsalkenyl-O—, alkynyl-O—, haloalkyl-O—, haloalkenyl-O—, haloalkynyl-O—,cycloalkyl-O—, cycloalkenyl-O—, halocycloalkyl-O—, andhalocycloalkenyl-O—, respectively, wherein alkenyl, alkynyl, haloalkyl,haloalkenyl, haloalkynyl, cycloalkyl, cycloalkenyl, halocycloalkyl, andhalocycloalkenyl are as defined above. Examples of C₁-C₆-alkoxy include,but are not limited to, methoxy, ethoxy, C₂H₅—CH₂O—, (CH₃)₂CHO—,n-butoxy, C₂H₅—CH(CH₃)O—, (CH₃)₂CH—CH₂O—, (CH₃)₃CO—, n-pentoxy,1-methylbutoxy, 2-methylbutoxy, 3-methylbutoxy, 1,1-dimethylpropoxy,1,2-dimethylpropoxy, 2,2-dimethyl-propoxy, 1-ethylpropoxy, n-hexoxy,1-methylpentoxy, 2-methylpentoxy, 3-methylpentoxy, 4-methylpentoxy,1,1-dimethylbutoxy, 1,2-dimethylbutoxy, 1,3-dimethylbutoxy,2,2-dimethylbutoxy, 2,3-dimethylbutoxy, 3,3-dimethylbutoxy,1-ethylbutoxy, 2-ethylbutoxy, 1, 1,2-trimethylpropoxy,1,2,2-trimethylpropoxy, 1-ethyl-1-methylpropoxy, 1-ethyl-2-methylpropoxyand the like.

The term “alkylthio” refers to alkyl-S—, wherein alkyl is as definedabove. Similarly, the terms “haloalkylthio,” “cycloalkylthio,” and thelike, refer to haloalkyl-S— and cycloalkyl-S— where haloalkyl andcycloalkyl are as defined above.

The term “alkylsulfinyl” refers to alkyl-S(O)—, wherein alkyl is asdefined above. Similarly, the term “haloalkylsulfinyl” refers tohaloalkyl-S(O)— where haloalkyl is as defined above.

The term “alkylsulfonyl” refers to alkyl-S(O)₂—, wherein alkyl is asdefined above. Similarly, the term “haloalkylsulfonyl” refers tohaloalkyl-S(O)₂— where haloalkyl is as defined above.

The term alkylamino and dialkylamino refer to alkyl-NH— and (alkyl)₂N—where alkyl is as defined above. Similarly, the terms “haloalkylamino”refers to haloalkyl-NH— where haloalkyl is as defined above.

The terms “alkylcarbonyl,” “alkoxycarbonyl,” “alkylaminocarbonyl,” and“dialkylaminocarbonyl” refer to alkyl-C(O)—, alkoxy-C(O)—,alkylamino-C(O)— and dialkylamino-C(O)— where alkyl, alkoxy, alkylaminoand dialkylamino are as defined above. Similarly, the terms“haloalkylcarbonyl,” “haloalkoxycarbonyl,” “haloalkylaminocarbonyl,” and“dihaloalkylaminocarbonyl” refer to the groups haloalkyl-C(O)—,haloalkoxy-C(O)—, haloalkylamino-C(O)— and dihaloalkylamino-C(O)— wherehaloalkyl, haloalkoxy, haloalkylamino and dihaloalkylamino are asdefined above.

“Aryl” refers to a monovalent aromatic carbocyclic group of from 6 to 14carbon atoms having a single ring or multiple condensed rings. In someembodiments, aryl groups include C₆-C₁₀ aryl groups. Aryl groupsinclude, but are not limited to, phenyl, biphenyl, naphthyl,tetrahydronaphtyl, phenylcyclopropyl and indanyl. Aryl groups may beunsubstituted or substituted by one or more moieties selected fromhalogen, cyano, nitro, hydroxy, mercapto, amino, alkyl, alkenyl,alkynyl, cycloalkyl, cycloalkenyl, haloalkyl, haloalkenyl, haloalkynyl,halocycloalkyl, halocycloalkenyl, alkoxy, alkenyloxy, alkynyloxy,haloalkoxy, haloalkenyloxy, haloalkynyl oxy, cycloalkoxy,cycloalkenyloxy, halocycloalkoxy, halocycloalkenyloxy, alkylthio,haloalkylthio, cycloalkylthio, halocycloalkylthio, alkylsulfinyl,alkenylsulfinyl, alkynyl-sulfinyl, haloalkylsulfinyl,haloalkenylsulfinyl, haloalkynylsulfinyl, alkylsulfonyl,alkenylsulfonyl, alkynyl sulfonyl, haloalkyl-sulfonyl, haloalkenylsulfonyl, haloalkynyl sulfonyl, alkylamino, alkenylamino, alkynylamino,di(alkyl)amino, di(alkenyl)-amino, di(alkynyl)amino, or trialkylsilyl.

The terms “aralkyl” or “arylalkyl” refers to an aryl group that isbonded to the parent compound through a diradical alkylene bridge,(—CH₂—)_(n), where n is 1-12 and where “aryl” is as defined above.

“Heteroaryl” refers to a monovalent aromatic group of from 1 to 15carbon atoms, preferably from 1 to 10 carbon atoms, having one or moreoxygen, nitrogen, and sulfur heteroatoms within the ring, preferably 1to 4 heteroatoms, or 1 to 3 heteroatoms. The nitrogen and sulfurheteroatoms may optionally be oxidized. Such heteroaryl groups can havea single ring (e.g., pyridyl or furyl) or multiple condensed ringsprovided that the point of attachment is through a heteroaryl ring atom.Preferred heteroaryls include pyridyl, piridazinyl, pyrimidinyl,pyrazinyl, triazinyl, pyrrolyl, indolyl, quinolinyl, isoquinolinyl,quinazolinyl, quinoxalinnyl, furanyl, thiophenyl, furyl, pyrrolyl,imidazolyl, oxazolyl, isoxazolyl, isothiazolyl, pyrazolyl benzofuranyl,and benzothiophenyl. Heteroaryl rings may be unsubstituted orsubstituted by one or more moieties as described for aryl above.

“Heterocyclyl,” “heterocyclic” or “heterocyclo” refer to fully saturatedor unsaturated, cyclic groups, for example, 3 to 7 membered monocyclicor 4 to 7 membered monocyclic; 7 to 11 membered bicyclic, or 10 to 15membered tricyclic ring systems, which have one or more oxygen, sulfuror nitrogen heteroatoms in ring, preferably 1 to 4 or 1 to 3heteroatoms. The nitrogen and sulfur heteroatoms may optionally beoxidized and the nitrogen heteroatoms may optionally be quaternized. Theheterocyclic group may be attached at any heteroatom or carbon atom ofthe ring or ring system and may be unsubstituted or substituted by oneor more moieties as described for aryl groups above.

Exemplary monocyclic heterocyclic groups include, but are not limitedto, pyrrolidinyl, pyrrolyl, pyrazolyl, oxetanyl, pyrazolinyl,imidazolyl, imidazolinyl, imidazolidinyl, oxazolyl, oxazolidinyl,isoxazolinyl, isoxazolyl, thiazolyl, thiadiazolyl, thiazolidinyl,isothiazolyl, isothiazolidinyl, furyl, tetrahydrofuryl, thienyl,oxadiazolyl, piperidinyl, piperazinyl, 2-oxopiperazinyl,2-oxopiperidinyl, 2-oxopyrrolodinyl, 2-oxoazepinyl, azepinyl,4-piperidonyl, pyridinyl, pyrazinyl, pyrimidinyl, pyridazinyl,tetrahydropyranyl, morpholinyl, thiamorpholinyl, thiamorpholinylsulfoxide, thiamorpholinyl sulfone, 1,3-dioxolane andtetrahydro-1,1-dioxothienyl, triazolyl, triazinyl, and the like.

Exemplary bicyclic heterocyclic groups include, but are not limited to,indolyl, benzothiazolyl, benzoxazolyl, benzodioxolyl, benzothienyl,quinuclidinyl, quinolinyl, tetra-hydroisoquinolinyl, isoquinolinyl,benzimidazolyl, benzopyranyl, indolizinyl, benzofuryl, chromonyl,coumarinyl, benzopyranyl, cinnolinyl, quinoxalinyl, indazolyl,pyrrolopyridyl, furopyridinyl (such as furo[2,3-c]pyridinyl,furo[3,2-b]pyridinyl] or furo[2,3-b]pyridinyl), dihydroisoindolyl,dihydroquinazolinyl (such as 3,4-dihydro-4-oxo-quinazolinyl),tetrahydroquinolinyl and the like.

Exemplary tricyclic heterocyclic groups include carbazolyl, benzidolyl,phenanthrolinyl, acridinyl, phenanthridinyl, xanthenyl, and the like.

Halogen means the atoms fluorine, chlorine, bromine and iodine. Thedesignation of “halo” (e.g. as illustrated in the term haloalkyl) refersto all degrees of substitutions from a single substitution to a perhalosubstitution (e.g. as illustrated with methyl as chloromethyl (—CH₂Cl),dichloromethyl (—CHCl₂), trichloromethyl (—CCl₃)).

Stereoisomers and Polymorphic Forms

It will be appreciated by those of skill in the art that certaincompounds within the compositions of the invention may exist and beisolated as optically active and racemic forms. Compounds having one ormore chiral centers, including at a sulfur atom, may be present assingle enantiomers or diastereomers or as mixtures of enantiomers and/ordiastereomers. For example, it is well known in the art that sulfoxidecompounds may be optically active and may exist as single enantiomers orracemic mixtures. In addition, compounds within the compositions of theinvention may include one or more chiral centers, which results in atheoretical number of optically active isomers. Where compounds withinthe compositions of the invention include n chiral centers, thecompounds may comprise up to 2^(n) optical isomers. The presentinvention encompasses the specific enantiomers or diastereomers of eachcompound as well as mixtures of different enantiomers and/ordiastereomers of the compounds of the invention that possess the usefulproperties described herein. The optically active forms can be preparedby, for example, resolution of the racemic forms by selectivecrystallization techniques, by synthesis from optically activeprecursors, by chiral synthesis, by chromatographic separation using achiral stationary phase or by enzymatic resolution.

The compounds within the compositions of present invention may also bepresent in different solid forms such as different crystalline forms orin the form of an amorphous solid. The present invention encompassesdifferent crystalline forms as well as amorphous forms of the inventivecompounds.

In addition, the compounds within the compositions of the invention mayexist as hydrates or solvates, in which a certain stoichiometric amountof water or a solvent is associated with the molecule in the crystallineform. The compositions of the invention may include hydrates andsolvates of the active agents. In some embodiments, the compositions ofthe invention may include up to 15% (w/w), up to 20% (w/w), or up to 30%(w/w) of a particular solid form.

Salts

Also contemplated within the scope of the invention are acid or basesalts, where applicable, of the compounds of the invention provided forherein.

The term “acid salt” contemplates salts of the compounds with allpharmaceutically acceptable inorganic or organic acids. Inorganic acidsinclude mineral acids such as hydrohalic acids such as hydrobromic acidand hydrochloric acid, sulfuric acid, phosphoric acids and nitric acid.Organic acids include all pharmaceutically acceptable aliphatic,alicyclic and aromatic carboxylic acids, dicarboxylic acids,tricarboxylic acids and fatty acids. In one embodiment of the acids, theacids are straight chain or branched, saturated or unsaturated C₁-C₂₀aliphatic carboxylic acids, which are optionally substituted by halogenor by hydroxyl groups, or C₆-C₁₂ aromatic carboxylic acids. Examples ofsuch acids are carbonic acid, formic acid, acetic acid, propionic acid,isopropionic acid, valeric acid, α-hydroxy acids such as glycolic acidand lactic acid, chloroacetic acid, benzoic acid, methane sulfonic acid,and salicylic acid. Examples of dicarboxylic acids include oxalic acid,malic acid, succinic acid, tartaric acid, fumaric acid, and maleic acid.An example of a tricarboxylic acid is citric acid. Fatty acids includeall pharmaceutically acceptable saturated or unsaturated aliphatic oraromatic carboxylic acids having 4 to 24 carbon atoms. Examples includebutyric acid, isobutyric acid, sec-butyric acid, lauric acid, palmiticacid, stearic acid, oleic acid, linoleic acid, linolenic acid, andphenylsteric acid. Other acids include gluconic acid, glycoheptonic acidand lactobionic acid.

The term “base salt” contemplates salts of the compounds with allpharmaceutically acceptable inorganic or organic bases, includinghydroxides, carbonates or bicarbonates of alkali metal or alkaline earthmetals. Salts formed with such bases include, for example, the alkalimetal and alkaline earth metal salts, including, but not limited to, asthe lithium, sodium, potassium, magnesium or calcium salts. Salts formedwith organic bases include the common hydrocarbon and heterocyclic aminesalts, which include, for example, ammonium salts (NH4⁺), alkyl- anddialkylammonium salts, and salts of cyclic amines such as the morpholineand piperidine salts.

In one embodiment, the invention provides topical veterinarycompositions comprising effective amounts of at least one isoxazoline offormula (I) below, in combination and a pharmaceutically or veterinarilyacceptable liquid carrier:

wherein

A¹, A², A³, A⁴, A⁵ and A⁶ are independently CR³ or N, provided that atmost 3 of A¹, A², A³, A⁴, A⁵ and A⁶ are N;

B¹, B² and B³ are independently CR² or N;

W is O or S;

R¹ is alkyl, alkenyl, alkynyl, cycloalkyl, alkylcycloalkyl orcycloalkylalkyl, each optionally substituted with one or moresubstituents independently selected from R⁶;

each R² is independently H, halogen, alkyl, haloalkyl, alkoxy,haloalkoxy, alkylthio, haloalkylthio, alkylsulfinyl, haloalkylsulfinyl,alkylsulfonyl, haloalkylsulfonyl, alkylamino, dialkylamino,alkoxycarbonyl, —CN or —NO₂;

each R³ is independently H, halogen, alkyl, haloalkyl, cycloalkyl,halocycloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio,alkylsulfinyl, haloalkylsulfinyl, alkylsulfonyl, haloalkylsulfonyl,alkylamino, dialkylamino, —CN or —NO₂;

R⁴ is H, alkyl, alkenyl, alkynyl, cycloalkyl, alkylcycloalkyl,cycloalkylalkyl, alkylcarbonyl or alkoxycarbonyl;

R⁵ is H, OR¹⁰, NR¹¹R¹² or Q¹; or alkyl, alkenyl, alkynyl, cycloalkyl,alkylcycloalkyl or cycloalkylalkyl, each optionally substituted with oneor more substituents independently selected from R⁷; or

R⁴ and R⁵ are taken together with the nitrogen to which they areattached to form a ring containing 2 to 6 atoms of carbon and optionallyone additional atom selected from the group consisting of N, S and O,said ring optionally substituted with 1 to 4 substituents independentlyselected from the group consisting of alkyl, halogen, —CN, —NO₂ andalkoxy;

each R⁶ is independently halogen, alkyl, alkoxy, alkylthio,alkylsulfinyl, alkylsulfonyl, —CN or —NO₂;

each R⁷ is independently halogen; alkyl, cycloalkyl, alkoxy, alkylthio,alkylsulfinyl, alkylsulfonyl, alkylamino, dialkylamino, cycloalkylamino,alkylcarbonyl, alkoxycarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl,haloalkylcarbonyl, haloalkoxycarbonyl, haloalkylaminocarbonyl,dihaloalkylaminocarbonyl, hydroxy, —NH₂, —CN or —NO₂; or Q²;

each R⁸ is independently halogen, alkoxy, haloalkoxy, alkylthio,haloalkylthio, alkylsulfinyl, haloalkylsulfinyl, alkylsulfonyl,haloalkylsulfonyl, alkylamino, dialkylamino, alkoxycarbonyl, —CN or—NO₂;

each R⁹ is independently halogen, alkyl, haloalkyl, cycloalkyl,halocycloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio,alkylsulfinyl, haloalkylsulfinyl, alkylsulfonyl, haloalkylsulfonyl,alkylamino, dialkylamino, —CN, —NO₂, phenyl or pyridinyl;

R¹⁰ is H; or alkyl, alkenyl, alkynyl, cycloalkyl, alkylcycloalkyl orcycloalkylalkyl, each optionally substituted with one of more halogen;

R¹¹ is H, alkyl, alkenyl, alkynyl, cycloalkyl, alkylcycloalkyl,cycloalkylalkyl, alkylcarbonyl or alkoxycarbonyl;

R¹² is H; Q³; or alkyl, alkenyl, alkynyl, cycloalkyl, alkylcycloalkyl orcycloalkylalkyl, each optionally substituted with one or moresubstituents independently selected from R⁷; or

R¹¹ and R¹² are taken together with the nitrogen to which they areattached to form a ring containing 2 to 6 atoms of carbon and optionallyone additional atom selected from the group consisting of N, S and O,said ring optionally substituted with 1 to 4 substituents independentlyselected from the group consisting of alkyl, halogen, —CN, —NO₂ andalkoxy;

Q¹ is a phenyl ring, a 5- or 6-membered heterocyclic ring, or an 8-, 9-or 10-membered fused bicyclic ring system optionally containing one tothree heteroatoms selected from up to 1 O, up to 1 S and up to 3 N, eachring or ring system optionally substituted with one or more substituentsindependently selected from R⁸;

each Q² is independently a phenyl ring or a 5- or 6-memberedheterocyclic ring, each ring optionally substituted with one or moresubstituents independently selected from R⁹;

Q³ is a phenyl ring or a 5- or 6-membered heterocyclic ring, each ringoptionally substituted with one or more substituents independentlyselected from R⁹; and

n is 0, 1 or 2.

In one embodiment, the invention provides topical veterinarycompositions comprising effective amounts of at least one isoxazoline offormula (I) below, in combination and a pharmaceutically or veterinarilyacceptable liquid carrier:

wherein:

A¹, A², A³, A⁴, A⁵ and A⁶ are independently CR³ or N, provided that atmost 3 of A¹, A², A³, A⁴, A⁵ and A⁶ are N;

B¹, B² and B³ are independently CR² or N;

W is O or S;

R¹ is C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₄-C₇alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, each optionally substitutedwith one or more substituents independently selected from R⁶;

each R² is independently H, halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₁-C₆alkoxy, C₁-C₆ haloalkoxy, C₁-C₆ alkylthio, C₁-C₆ haloalkylthio, C₁-C₆alkylsulfinyl, C₁-C₆ haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆haloalkylsulfonyl, C₁-C₆ alkylamino, C₂-C₆ dialkylamino, C₂-C₄alkoxycarbonyl, —CN or —NO₂;

each R³ is independently H, halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₃-C₆cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, —CN or —NO₂;

R⁴ is H, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₄-C₇ alkylcycloalkyl, C₄-C₇ cycloalkylalkyl, C₂-C₇ alkylcarbonyl orC₂-C₇ alkoxycarbonyl;

R⁵ is H, OR¹⁰, NR¹¹R¹² or Q¹; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇cycloalkylalkyl, each optionally substituted with one or moresubstituents independently selected from R⁷; or

R⁴ and R⁵ are taken together with the nitrogen to which they areattached to form a ring containing 2 to 6 atoms of carbon and optionallyone additional atom selected from the group consisting of N, S and O,said ring optionally substituted with 1 to 4 substituents independentlyselected from the group consisting of C₁-C₂ alkyl, halogen, —CN, —NO₂and C₁-C₂ alkoxy;

each R⁶ is independently halogen, C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆alkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆ alkylsulfonyl, —CN or —NO₂;

each R⁷ is independently halogen; C₁-C₆ alkyl, C₃-C₆ cycloalkyl, C₁-C₆alkoxy, C₁-C₆ alkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆alkylamino, C₂-C₈ dialkylamino, C₃-C₆ cycloalkylamino, C₂-C₇alkylcarbonyl, C₂-C₇ alkoxycarbonyl, C₂-C₇ alkylaminocarbonyl, C₃-C₉dialkylaminocarbonyl, C₂-C₇ haloalkylcarbonyl, C₂-C₇ haloalkoxycarbonyl,C₂-C₇ haloalkylaminocarbonyl, C₃-C₉ dihaloalkylaminocarbonyl, hydroxy,—NH₂, —CN or —NO₂; or Q²;

each R⁸ is independently halogen, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, C₂-C₄ alkoxycarbonyl, —CN or —NO₂;

each R⁹ is independently halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₃-C₆cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, —CN, —NO₂, phenyl or pyridinyl;

R¹⁰ is H; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, eachoptionally substituted with one of more halogen;

R¹¹ is H, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₄-C₇ alkylcycloalkyl, C₄-C₇ cycloalkylalkyl, C₂-C₇ alkylcarbonyl orC₂-C₇ alkoxycarbonyl;

R¹² is H; Q³; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, eachoptionally substituted with one or more substituents independentlyselected from R⁷; or

R¹¹ and R¹² are taken together with the nitrogen to which they areattached to form a ring containing 2 to 6 atoms of carbon and optionallyone additional atom selected from the group consisting of N, S and O,said ring optionally substituted with 1 to 4 substituents independentlyselected from the group consisting of C₁-C₂ alkyl, halogen, —CN, —NO₂and C₁-C₂ alkoxy;

Q¹ is a phenyl ring, a 5- or 6-membered heterocyclic ring, or an 8-, 9-or 10-membered fused bicyclic ring system optionally containing one tothree heteroatoms selected from up to 1 O, up to 1 S and up to 3 N, eachring or ring system optionally substituted with one or more substituentsindependently selected from R⁸;

each Q² is independently a phenyl ring or a 5- or 6-memberedheterocyclic ring, each ring optionally substituted with one or moresubstituents independently selected from R⁹;

Q³ is a phenyl ring or a 5- or 6-membered heterocyclic ring, each ringoptionally substituted with one or more substituents independentlyselected from R⁹; and

n is 0, 1 or 2.

In one embodiment of formula (I), W is O. In another embodiment, W is S.

In another embodiment of formula (I), A², A³, A⁴, A⁵ and A⁶ are eachCR³.

In another embodiment of formula (I), B¹, B² and B³ are each CR².

In still another embodiment of formula (I), W is O and A², A³, A⁴, A⁵and A⁶ are each CR³.

In yet another embodiment of formula (I), W is O; A¹, A², A³, A⁴, A⁵ andA⁶ are each CR³; and B¹, B² and B³ are each CR².

In another embodiment of formula (I), A², A³, A⁴, A⁵ and A⁶ are each CH.

In another embodiment of formula (I), B¹, B² and B³ are each CR²; and R²is H, halogen, C₁-C₆ alkyl or C₁-C₆ haloalkyl.

In still another embodiment of formula (I), R¹ is C₁-C₃ alkyl optionallysubstituted by one or more of R⁶;

R² is independently H, halogen, C₁-C₆ haloalkyl, C₁-C₆ haloalkoxy or—CN; and

each R³ is independently H, halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₃-C₆cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, —CN or—NO₂.

In still another embodiment, the invention provides a compositioncomprising an isoxazoline of formula (I) wherein:

-   -   W is O or S; R⁴ is H or C₁-C₆ alkyl; R⁵ is —CH₂C(O)NHCH₂CF₃;        each of    -   A¹=A²=A³=A⁴=A⁵=A⁶ is CH;    -   R¹ is C₁-C₆ alkyl each optionally substituted with one or more        substituents independently selected from R⁶;    -   R⁶ is halogen or C₁-C₆ alkyl; and    -   B¹, B², and B³ are independently CH, C-halogen, C—C₁-C₆ alkyl,        C—C₁-C₆ haloalkyl, or C—C₁-C₆ alkoxy.

In another embodiment of formula (I), B¹, B² and B³ are independentlyCR²;

W is O;

R⁴ is H, C₁-C₆ alkyl, C₂-C₇ alkylcarbonyl or C₂-C₇ alkoxycarbonyl; and

R⁵ is H, NR¹¹R¹² or Q¹; or C₁-C₄ alkyl, C₂-C₄ alkenyl, C₂-C₄ alkynyl,C₃-C₄ cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, eachoptionally substituted with one or more of R⁷.

In still another embodiment of formula (I), R¹ is C₁-C₃ alkyl optionallysubstituted with halogen;

each R² is independently H, CF₃, OCF₃, halogen or —CN;

each R³ is independently H, C₁-C₄ alkyl, C₁-C₄ haloalkyl, C₃-C₆cycloalkyl, C₁-C₄ alkoxy or —CN; and

each R⁷ is independently halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄alkylthio, C₁-C₄ alkylsulfinyl, C₁-C₄ alkylsulfonyl, C₂-C₄alkylcarbonyl, C₂-C₄ alkoxycarbonyl, C₂-C₅ alkylaminocarbonyl, C₂-C₅haloalkylcarbonyl, C₂-C₅ haloalkoxycarbonyl, C₂-C₅haloalkylaminocarbonyl, —NH₂, —CN or NO₂; or Q₂.

In yet another embodiment of formula (I), R⁴ is H;

R⁵ is C₁-C₄ alkyl optionally substituted with one or more R⁷;

each R⁷ is independently halogen or Q²; and

each Q² is independently phenyl, pyridinyl or thiazolyl.

In still another embodiment of formula (I), R¹ is CF₃;

A¹, A², A³, A⁴, A⁵ and A⁶ are each CR³;

B² is CR²; and

each R³ is independently H, C₁-C₄ alkyl or —CN.

In another embodiment, B² is CH;

B¹ and B³ are each CR² where each R² is independently halogen or C₁-C₃haloalkyl;

A¹, A², A³, A⁴, A⁵ and A⁶ are each CR³.

R³ is H; and

n is 2.

In still another embodiment of formula (I), R¹ is CF₃;

A¹, A², A³, A⁴, A⁵ and A⁶ are each CR³;

B² is CH;

each of B¹ and B³ are CR²;

each R³ is independently H or C₁-C₄ alkyl;

each R² is independently halogen or C₁-C₃ haloalkyl;

R⁴ is H;

R⁵ is C₁-C₄ alkyl optionally substituted with one or more R⁷; and

R⁷ is C₂-C₇ alkylcarbonyl, C₂-C₇ alkoxycarbonyl, C₂-C₇alkylaminocarbonyl, C₃-C₉ dialkylaminocarbonyl, C₂-C₇ haloalkylcarbonyl,C₂-C₇ haloalkoxycarbonyl, C₂-C₇ haloalkylaminocarbonyl, C₃-C₉dihaloalkylaminocarbonyl.

In yet another embodiment of formula (I), R¹ is CF₃;

A¹, A², A³, A⁴, A⁵ and A⁶ are each CH;

B² is CH;

each of B¹ and B³ are CR²;

each R² is independently halogen or C₁-C₃ haloalkyl;

R⁴ is H;

R⁵ is C₁-C₄ alkyl optionally substituted with one or more R⁷; and

R⁷ is C₂-C₇ alkylaminocarbonyl, C₃-C₉ dialkylaminocarbonyl, C₂-C₇haloalkylaminocarbonyl or C₃-C₉ dihaloalkylaminocarbonyl.

In a preferred embodiment, a topical composition comprising anisoxazoline active agent of formula (I) is provided, wherein:

R¹ is CF₃;

W is O;

A¹, A², A³, A⁴, A⁵ and A⁶ are each CH;

B² is CH;

B¹ is chloro;

B² is CF3;

R⁴ is H;

R⁵ is CH₂C(O)NHCH₂CF₃; and

n is 2.

In a preferred embodiment, the isoxazoline compound is4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamide(Compound A).

In another embodiment, the compositions of the invention may include oneor more compounds of the isoxazolines disclosed in WO 2007/079162, WO2007/075459 and US 2009/0133319, WO 2007/070606 and US 2009/0143410, WO2009/003075, WO 2009/002809, WO 2009/024541, WO 2005/085216 and US2007/0066617 and WO 2008/122375, all of which are incorporated herein byreference in their entirety.

In other preferred embodiments, the invention provides topicalcompositions comprising an isoxazoline active agent described in WO2009/02451A2 and WO 2011/075591A1, both incorporated herein by referencein their entirety, in combination with a pharmaceutically acceptablecarrier or diluent.

In another preferred embodiment, the invention provides topicalcompositions comprising compound 11-1 described in WO 2009/02451A2,which has the structure:

in combination with a pharmaceutically acceptable carrier or diluentdescribed herein.

In still another embodiment the invention provides topical compositionscomprising one or more of the isoxazoline compounds of formulae 1.001 to1.025 and 2.001 to 2.018 described in WO 2011075591 in combination witha pharmaceutically acceptable carrier described herein:

Compounds 1.001 to 1.025

Compound MS RT LCMS No. (Z)_(p) B⁵ B⁴ B³ B² B¹ R¹⁵ R¹⁶ MH⁺ (min) Method1.001 3,5-Cl₂ C—H C—H C—H C—H N H CH₂C(O)NHCH₂CF₃ 582 2.21 1 1.0023,5-Cl₂ C—H C—H C—H C—H N H CH₂CF₃ 525 2.32 1 1.003 3,5-(CF₃)₂ C—H C—HC—H C—H N CH₃ CH₂CO₂CH₃ 597 2.06 1 1.004 3,5-(CF₃)₂ C—H C—H C—H C—H NCH₃ CH₂CO₂H 583 2.07 1 1.005 3,5-(CF₃)₂ C—H C—H C—H C—H N CH₃CH₂C(O)NHCH₂CF₃ 664 2.14 1 1.006 3,5-(CF₃)₂ C—H C—H C—H C—H N HCH₂C(O)NHCH₂CF₃ 650 2.18 1 1.007 3,5-(CF₃)₂ C—H C—H C—H C—H N HCH₂CH₂SCH₃ 585 2.31 1 1.008 3,5-(CF₃)₂ C—H C—H C—H C—H C—H HCH₂C(O)NHCH₂CF₃ 648 2.18 1 1.009 3,5-(CF₃)₂ C—H C—H C—H C—H C—H HCH₂CH₂SCH₃ 584 2.24 1 1.010 3,5-(CF₃)₂ C—H C—H C—H C—H C—H H CH₂CF₃1.011 3,5-Cl₂ C—H C—H C—H C—H C—H H CH₂C(O)NHCH₂CF₃ 581 2.20 1 1.0123,5-Cl₂ C—H C—H C—H C—H C—H H CH₂CF₃ 1.013 3,5-Cl₂ C—H C—H C—H C—H C—H HCH₂CH₂SCH₃ 516 2.26 1 1.014 3-Cl,5-CF₃ C—H C—H C—H C—H C—H HCH₂C(O)NHCH₂CF₃ 1.015 3-Cl,5-CF₃ C—H C—H C—H C—H C—H H CH₂CF₃ 1.0163-Cl,5-CF₃ C—H C—H C—H C—H C—H H CH₂CH₂SCH₃ 1.017 3,5-Cl₂ C—H C—H C—MeC—H C—Me H CH₂C(O)NHCH₂CF₃ 609 2.12 1 1.018 3,5-Cl₂ C—H C—H C—Me C—HC—Me H CH₂CF₃ 552 2.17 1 1.019 3,5-Cl₂ C—H C—H C—Me C—H C—Me HCH₂CH₂SCH₃ 544 2.18 1 1.020 3,5-(CF₃)₂ C—H C—H C—Me C—H C—Me HCH₂C(O)NHCH₂CF₃ 1.021 3,5-(CF₃)₂ C—H C—H C—Me C—H C—Me H CH₂CF₃ 1.0223,5-(CF₃)₂ C—H C—H C—Me C—H C—Me H CH₂CH₂SCH₃ 1.023 3-Cl,5-CF₃ C—H C—HC—Me C—H C—Me H CH₂C(O)NHCH₂CF₃ 1.024 3-Cl,5-CF₃ C—H C—H C—Me C—H C—Me HCH₂CF₃ 1.025 3-Cl,5-CF₃ C—H C—H C—Me C—H C—Me H CH₂CH₂SCH₃

Compounds 2.001 to 2.018

Compound MS RT LCMS No. (Z)_(p) B⁵ B⁴ B³ B² B¹ R¹⁵ R¹⁶ MH⁺ (min) Method2.001 3,5-Cl₂ C—H C—H N C—H C—H H CH₂C(O)NHCH₂CF₃ 2.002 3,5-Cl₂ C—H C—HN C—H C—H H CH₂CF₃ 2.003 3,5-Cl₂ C—H C—H N C—H C—H H CH₂CH₂SCH₃ 2.0043,5-(CF₃)₂ C—H C—H N C—H C—H H CH₂C(O)NHCH₂CF₃ 650 1.85 1 2.0053,5-(CF₃)₂ C—H C—H N C—H C—H H CH₂CF₃ 2.006 3,5-(CF₃)₂ C—H C—H N C—H C—HH CH₂CH₂SCH₃ 2.007 3-Cl,5-CF₃ C—H C—H N C—H C—H H CH₂C(O)NHCH₂CF₃ 2.0083-Cl,5-CF₃ C—H C—H N C—H C—H H CH₂CF₃ 2.009 3-Cl,5-CF₃ C—H C—H N C—H C—HH CH₂CH₂SCH₃ 2.010 3,5-Cl₂ C—H C—H C—H C—H C—H H CH₂C(O)NHCH₂CF₃ 2.0113,5-Cl₂ C—H C—H C—H C—H C—H H CH₂CF₃ 2.012 3,5-Cl₂ C—H C—H C—H C—H C—H HCH₂CH₂SCH₃ 2.013 3,5-(CF₃)₂ C—H C—H C—H C—H C—H H CH₂C(O)NHCH₂CF₃ 2.0143,5-(CF₃)₂ C—H C—H C—H C—H C—H H CH₂CF₃ 2.015 3,5-(CF₃)₂ C—H C—H C—H C—HC—H H CH₂CH₂SCH₃ 2.016 3-Cl,5-CF₃ C—H C—H C—H C—H C—H H CH₂C(O)NHCH₂CF₃2.017 3-Cl,5-CF₃ C—H C—H C—H C—H C—H H CH₂CF₃ 2.018 3-Cl,5-CF₃ C—H C—HC—H C—H C—H H CH₂CH₂SCH₃

In one embodiment, the invention provides a topical compositioncomprising at least one isoxazoline of formula (I) in combination atleast one other active agent, and a pharmaceutically acceptable carrieror diluent.

Additional veterinary/pharmaceutical active ingredients may be used withthe compositions of the invention. In some embodiments, the additionalactive agents may include, but are not limited to, acaricides,anthelmintics, anti-parasitics and insecticides. Anti-parasitic agentscan include both ectoparasiticidal and/or endoparasiticidal agents.

Veterinary pharmaceutical agents that may be included in thecompositions of the invention are well-known in the art (see e.g. Plumb′Veterinary Drug Handbook, 5^(th) Edition, ed. Donald C. Plumb, BlackwellPublishing, (2005) or The Merck Veterinary Manual, 9^(th) Edition,(January 2005)) and include but are not limited to acarbose,acepromazine maleate, acetaminophen, acetazolamide, acetazolamidesodium, acetic acid, acetohydroxamic acid, acetylcysteine, acitretin,acyclovir, albendazole, albuterol sulfate, alfentanil, allopurinol,alprazolam, altrenogest, amantadine, amikacin sulfate, aminocaproicacid, aminopentamide hydrogen sulfate, aminophylline/theophylline,amiodarone, amitriptyline, amlodipine besylate, ammonium chloride,ammonium molybdenate, amoxicillin, clavulanate potassium, amphotericin Bdesoxycholate, amphotericin B lipid-based, ampicillin, amprolium,antacids (oral), antivenin, apomorphione, apramycin sulfate, ascorbicacid, asparaginase, aspiring, atenolol, atipamezole, atracuriumbesylate, atropine sulfate, aurnofin, aurothioglucose, azaperone,azathioprine, azithromycin, baclofen, barbituates, benazepril,betamethasone, bethanechol chloride, bisacodyl, bismuth sub salicylate,bleomycin sulfate, boldenone undecylenate, bromides, bromocriptinemesylate, budenoside, buprenorphine, buspirone, busulfan, butorphanoltartrate, cabergoline, calcitonin salmon, calcitrol, calcium salts,captopril, carbenicillin indanyl sodium, carbimazole, carboplatin,carnitine, carprofen, carvedilol, cefadroxil, cefazolin sodium,cefixime, clorsulon, cefoperazone sodium, cefotaxime sodium, cefotetandisodium, cefoxitin sodium, cefpodoxime proxetil, ceftazidime, ceftiofursodium, ceftiofur, ceftiaxone sodium, cephalexin, cephalosporins,cephapirin, charcoal (activated), chlorambucil, chloramphenicol,chlordiazepoxide, chlordiazepoxide +/− clidinium bromide,chlorothiazide, chlorpheniramine maleate, chlorpromazine,chlorpropamide, chlortetracycline, chorionic gonadotropin (HCG),chromium, cimetidine, ciprofloxacin, cisapride, cisplatin, citratesalts, clarithromycin, clemastine fumarate, clenbuterol, clindamycin,clofazimine, clomipramine, claonazepam, clonidine, cloprostenol sodium,clorazepate dipotassium, clorsulon, cloxacillin, codeine phosphate,colchicine, corticotropin (ACTH), cosyntropin, cyclophosphamide,cyclosporine, cyproheptadine, cytarabine, dacarbazine,dactinomycin/actinomycin D, dalteparin sodium, danazol, dantrolenesodium, dapsone, decoquinate, deferoxamine mesylate, deracoxib,deslorelin acetate, desmopressin acetate, desoxycorticosterone pivalate,detomidine, dexamethasone, dexpanthenol, dexraazoxane, dextran,diazepam, diazoxide (oral), dichlorphenamide, diclofenac sodium,dicloxacillin, diethylcarbamazine citrate, diethylstilbestrol (DES),difloxacin, digoxin, dihydrotachysterol (DHT), diltiazem,dimenhydrinate, dimercaprol/BAL, dimethyl sulfoxide, dinoprosttromethamine, diphenylhydramine, disopyramide phosphate, dobutamine,docusate/DSS, dolasetron mesylate, domperidone, dopamine, doramectin,doxapram, doxepin, doxorubicin, doxycycline, edetate calciumdisodium.calcium EDTA, edrophonium chloride, enalapril/enalaprilat,enoxaparin sodium, enrofloxacin, ephedrine sulfate, epinephrine,epoetin/erythropoietin, eprinomectin, epsiprantel, erythromycin,esmolol, estradiol cypionate, ethacrynic acid/ethacrynate sodium,ethanol (alcohol), etidronate sodium, etodolac, etomidate, euthanasiaagents w/pentobarbital, famotidine, fatty acids (essential/omega),felbamate, fentanyl, ferrous sulfate, filgrastim, finasteride, fipronil,florfenicol, fluconazole, flucytosine, fludrocortisone acetate,flumazenil, flumethasone, flunixin meglumine, fluorouracil (5-FU),fluoxetine, fluticasone propionate, fluvoxamine maleate, fomepizole(4-MP), furazolidone, furosemide, gabapentin, gemcitabine, gentamicinsulfate, glimepiride, glipizide, glucagon, glucocorticoid agents,glucosamine/chondroitin sulfate, glutamine, glyburide, glycerine (oral),glycopyrrolate, gonadorelin, grisseofulvin, guaifenesin, halothane,hemoglobin glutamer-200 (OXYGLOBIN®®), heparin, hetastarch, hyaluronatesodium, hydrazaline, hydrochlorothiazide, hydrocodone bitartrate,hydrocortisone, hydromorphone, hydroxyurea, hydroxyzine, ifosfamide,imidacloprid, imidocarb dipropinate, impenem-cilastatin sodium,imipramine, inamrinone lactate, insulin, interferon alfa-2a (humanrecombinant), iodide (sodium/potassium), ipecac (syrup), ipodate sodium,iron dextran, isoflurane, isoproterenol, isotretinoin, isoxsuprine,itraconazole, ivermectin, kaolin/pectin, ketamine, ketoconazole,ketoprofen, ketorolac tromethamine, lactulose, leuprolide, levami sole,levetiracetam, levothyroxine sodium, lidocaine, lincomycin, liothyroninesodium, lisinopril, lomustine (CCNU), lufenuron, lysine, magnesium,mannitol, marbofloxacin, mechlorethamine, meclizine, meclofenamic acid,medetomidine, medium chain triglycerides, medroxyprogesterone acetate,megestrol acetate, melarsomine, melatonin, meloxican, melphalan,meperidine, mercaptopurine, meropenem, metformin, methadone,methazolamide, methenamine mandelate/hippurate, methimazole, methionine,methocarbamol, methohexital sodium, methotrexate, methoxyflurane,methylene blue, methylphenidate, methylprednisolone, metoclopramide,metoprolol, metronidaxole, mexiletine, mibolerlone, midazolam milbemycinoxime, mineral oil, minocycline, misoprostol, mitotane, mitoxantrone,morphine sulfate, moxidectin, naloxone, mandrolone decanoate, naproxen,narcotic (opiate) agonist analgesics, neomycin sulfate, neostigmine,niacinamide, nitazoxanide, nitenpyram, nitrofurantoin, nitroglycerin,nitroprusside sodium, nizatidine, novobiocin sodium, nystatin,octreotide acetate, olsalazine sodium, omeprozole, ondansetron, opiateantidiarrheals, orbifloxacin, oxacillin sodium, oxazepam, oxibutyninchloride, oxymorphone, oxytretracycline, oxytocin, pamidronate disodium,pancreplipase, pancuronium bromide, paromomycin sulfate, parozetine,pencillamine, general information penicillins, penicillin G, penicillinV potassium, pentazocine, pentobarbital sodium, pentosan polysulfatesodium, pentoxifylline, pergolide mesylate, phenobarbital,phenoxybenzamine, pheylbutazone, phenylephrine, phenypropanolamine,phenytoin sodium, pheromones, parenteral phosphate, phytonadione/vitaminK-1, pimobendan, piperazine, pirlimycin, piroxicam, polysulfatedglycosaminoglycan, ponazuril, potassium chloride, pralidoxime chloride,prazosin, predni solone/predni sone, primidone, procainamide,procarbazine, prochlorperazine, propantheline bromide, propionibacteriumacnes injection, propofol, propranolol, protamine sulfate,pseudoephedrine, psyllium hydrophilic mucilloid, pyridostigmine bromide,pyrilamine maleate, pyrimethamine, quinacrine, quinidine, ranitidine,rifampin, s-adenosyl-methionine (SAMe), saline/hyperosmotic laxative,selamectin, selegiline/l-deprenyl, sertraline, sevelamer, sevoflurane,silymarin/milk thistle, sodium bicarbonate, sodium polystyrenesulfonate, sodium stibogluconate, sodium sulfate, sodum thiosulfate,somatotropin, sotalol, spectinomycin, spironolactone, stanozolol,streptokinase, streptozocin, succimer, succinylcholine chloride,sucralfate, sufentanil citrate, sulfachlorpyridazine sodium,sulfadiazine/trimethroprim, sulfamethoxazole/trimethoprim,sulfadimentoxine, sulfadimethoxine/ormetoprim, sulfasalazine, taurine,tepoxaline, terbinafline, terbutaline sulfate, testosterone,tetracycline, thiacetarsamide sodium, thiamine, thioguanine, thiopentalsodium, thiotepa, thyrotropin, tiamulin, ticarcilin disodium,tiletamine/zolazepam, tilmocsin, tiopronin, tobramycin sulfate,tocainide, tolazoline, telfenamic acid, topiramate, tramadol,trimcinolone acetonide, trientine, trilostane, trimepraxine tartratew/prednisolone, tripelennamine, tylosin, urdosiol, valproic acid,vanadium, vancomycin, vasopressin, vecuronium bromide, verapamil,vinblastine sulfate, vincristine sulfate, vitamin E/selenium, warfarinsodium, xylazine, yohimbine, zafirlukast, zidovudine (AZT), zincacetate/zinc sulfate, zonisamide and mixtures thereof.

In one embodiment of the invention, arylpyrazole compounds such asphenylpyrazoles, known in the art may be combined with the isoxazolinecompounds in the topical compositions of the invention. Examples of sucharylpyrazole compounds include but are not limited to those described inU.S. Pat. Nos. 6,001,384; 6,010,710; 6,083,519; 6,096,329; 6,174,540;6,685,954 and 6,998,131 (all of which are incorporated herein byreference, each assigned to Merial, Ltd., Duluth, Ga.).

In another embodiment of the invention, one or more macrocyclic lactonesor lactams, which act as an acaricide, anthelmintic agent and/orinsecticide, can be added to the compositions of the invention.

The macrocyclic lactones include, but are not limited to, avermectinssuch as abamectin, dimadectin, doramectin, emamectin, eprinomectin,ivermectin, latidectin, lepimectin, selamectin and ML-1,694,554, andmilbemycins such as milbemectin, milbemycin D, moxidectin andnemadectin. Also included are the 5-oxo and 5-oxime derivatives of saidavermectins and milbemycins. Examples of combinations of arylpyrazolecompounds with macrocyclic lactones include but are not limited to thosedescribed in U.S. Pat. Nos. 6,426,333; 6,482,425; 6,962,713 and6,998,131 (all incorporated herein by reference—each assigned to Merial,Ltd., Duluth, Ga.).

The macrocyclic lactone compounds are known in the art and can easily beobtained commercially or through synthesis techniques known in the art.Reference is made to the widely available technical and commercialliterature. For avermectins, ivermectin and abamectin, reference may bemade, for example, to the work “Ivermectin and Abamectin”, 1989, by M.H. Fischer and H. Mrozik, William C. Campbell, published by SpringerVerlag., or Albers-Schönberg et al. (1981), “Avermectins StructureDetermination”, J. Am. Chem. Soc., 103, 4216-4221. For doramectin,“Veterinary Parasitology”, vol. 49, No. 1, July 1993, 5-15 may beconsulted. For milbemycins, reference may be made, inter alia, to DaviesH. G. et al., 1986, “Avermectins and Milbemycins”, Nat. Prod. Rep., 3,87-121, Mrozik H. et al., 1983, Synthesis of Milbemycins fromAvermectins, Tetrahedron Lett., 24, 5333-5336, U.S. Pat. No. 4,134,973and EP 0 677 054.

Macrocyclic lactones are either natural products or are semi-syntheticderivatives thereof. The structure of the avermectins and milbemycinsare closely related, e.g., by sharing a complex 16-membered macrocycliclactone ring. The natural product avermectins are disclosed in U.S. Pat.No. 4,310,519 and the 22,23-dihydro avermectin compounds are disclosedin U.S. Pat. No. 4,199,569. Mention is also made of U.S. Pat. Nos.4,468,390, 5,824,653, EP 0 007 812 A1, U.K. Patent Specification 1 390336, EP 0 002 916, and New Zealand Patent No. 237 086, inter alia.Naturally occurring milbemycins are described in U.S. Pat. No. 3,950,360as well as in the various references cited in “The Merck Index” 12^(th)ed., S. Budavari, Ed., Merck & Co., Inc. Whitehouse Station, N.J.(1996). Latidectin is described in the “International NonproprietaryNames for Pharmaceutical Substances (INN)”, WHO Drug Information, vol.17, no. 4, pp. 263-286, (2003). Semisynthetic derivatives of theseclasses of compounds are well known in the art and are described, forexample, in U.S. Pat. Nos. 5,077,308, 4,859,657, 4,963,582, 4,855,317,4,871,719, 4,874,749, 4,427,663, 4,310,519, 4,199,569, 5,055,596,4,973,711, 4,978,677, 4,920,148 and EP 0 667 054.

In preferred embodiment of the invention, the invention comprises atopical composition comprising an isoxazoline compound in combinationwith a class of acaricides or insecticides known as insect growthregulators (IGRs). Compounds belonging to this group are well known tothe practitioner and represent a wide range of different chemicalclasses. These compounds all act by interfering with the development orgrowth of the insect pests. Insect growth regulators are described, forexample, in U.S. Pat. Nos. 3,748,356, 3,818,047, 4,225,598, 4,798,837,4,751,225, EP 0 179 022 or U.K. 2 140 010 as well as U.S. Pat. Nos.6,096,329 and 6,685,954 (all incorporated herein by reference).

In one embodiment the IGR is a compound that mimics juvenile hormone.Examples of juvenile hormone mimics include azadirachtin, diofenolan,fenoxycarb, hydroprene, kinoprene, methoprene, pyriproxyfen,tetrahydroazadirachtin and4-chloro-2(2-chloro-2-methyl-propyl)-5-(6-iodo-3-pyridylmethoxy)pyridazine-3(2H)-one.

In a particularly preferred embodiment, the compositions of theinvention comprise an isoxazoline compound of formula (I) in combinationwith methoprene or pyriproxyfen and a pharmaceutically acceptablecarrier. It has been surprisingly found that compositions comprising anisoxazoline compound of formula (I) in combination with methoprene orpyriproxyphen exhibit superior long lasting efficacy that is notpredictable based on the activity of each active alone.

In another embodiment, the IGR compound is a chitin synthesis inhibitor.Chitin synthesis inhibitors include chlorofluazuron, cyromazine,diflubenzuron, fluazuron, flucycloxuron, flufenoxuron, hexaflumoron,lufenuron, tebufenozide, teflubenzuron, triflumoron, novaluron,1-(2,6-difluorobenzoyl)-3-(2-fluoro-4-(trifluoromethyl)phenylurea,1-(2,6-difluorobenzoyl)-3-(2-fluoro-4-(1,1,2,2-tetrafluoroethoxy)-phenylureaand 1-(2, 6-difluorobenzoyl)-3-(2-fluoro-4-trifluoromethyl)phenylurea.

In yet another embodiment of the invention, adulticide insecticides andacaricides can also be added to the composition of the invention. Theseinclude pyrethrins (which include cinerin I, cinerin II, jasmolin I,jasmolin II, pyrethrin I, pyrethrin II and mixtures thereof) andpyrethroids, and carbamates including, but are not limited to, benomyl,carbanolate, carbaryl, carbofuran, meththiocarb, metolcarb, promacyl,propoxur, aldicarb, butocarboxim, oxamyl, thiocarboxime and thiofanox.

In some embodiments, the compositions of the invention may include oneor more antinematodal agents including, but not limited to, activeagents in the benzimidazoles, imidazothiazoles, tetrahydropyrimidines,and organophosphate class of compounds. In some embodiments,benzimidazoles including, but not limited to, thiabendazole,cambendazole, parbendazole, oxibendazole, mebendazole, flubendazole,fenbendazole, oxfendazole, albendazole, cyclobendazole, febantel,thiophanate and its o,o-dimethyl analogue may be included in thecompositions.

In other embodiments, the compositions may include an imidazothiazolecompounds including, but not limited to, tetramisole, levamisole andbutamisole. In still other embodiments, the compositions of theinvention may include tetrahydropyrimidine active agents including, butnot limited to, pyrantel, oxantel, and morantel. Suitableorganophosphate active agents include, but are not limited to,coumaphos, trichlorfon, haloxon, naftalofos and dichlorvos, heptenophos,mevinphos, monocrotophos, TEPP, and tetrachlorvinphos.

In other embodiments, the compositions may include the antinematodalcompounds phenothiazine and piperazine as the neutral compound or invarious salt forms, diethylcarbamazine, phenols such as disophenol,arsenicals such as arsenamide, ethanolamines such as bephenium, theniumclosylate, and methyridine; cyanine dyes including pyrvinium chloride,pyrvinium pamoate and dithiazanine iodide; isothiocyanates includingbitoscanate, suramin sodium, phthalofyne, and various natural productsincluding, but not limited to, hygromycin B, α-santonin and kainic acid.

In other embodiments, the compositions of the invention may includeantitrematodal agents. Suitable antitrematodal agents include, but arenot limited to, the miracils such as miracil D and mirasan;praziquantel, clonazepam and its 3-methyl derivative, oltipraz,lucanthone, hycanthone, oxamniquine, amoscanate, niridazole, nitroxynil,various bisphenol compounds known in the art including hexachlorophene,bithionol, bithionol sulfoxide and menichlopholan; varioussalicylanilide compounds including tribromsalan, oxyclozanide,clioxanide, rafoxanide, brotianide, bromoxanide and closantel;triclabendazole, diamfenetide, clorsulon, hetolin and emetine.

Anticestodal compounds may also be advantageously used in thecompositions of the invention including, but not limited to, arecolinein various salt forms, bunamidine, niclosamide, nitroscanate,paromomycin and paromomycin II.

In yet other embodiments, the compositions of the invention may includeother active agents that are effective against arthropod parasites.Suitable active agents include, but are not limited to, bromocyclen,chlordane, DDT, endosulfan, lindane, methoxychlor, toxaphene, bromophos,bromophos-ethyl, carbophenothion, chlorfenvinphos, chlorpyrifos,crotoxyphos, cythioate, diazinon, dichlorenthion, diemthoate,dioxathion, ethion, famphur, fenitrothion, fenthion, fospirate,iodofenphos, malathion, naled, phosalone, phosmet, phoxim, propetamphos,ronnel, stirofos, allethrin, cyhalothrin, cypermethrin, deltamethrin,fenvalerate, flucythrinate, permethrin, phenothrin, pyrethrins,resmethrin, benzyl benzoate, carbon disulfide, crotamiton,diflubenzuron, diphenylamine, disulfiram, isobornyl thiocyanato acetate,methoprene, monosulfiram, pirenonylbutoxide, rotenone, triphenyltinacetate, triphenyltin hydroxide, deet, dimethyl phthalate, and thecompounds 1,5a,6,9,9a,9b-hexahydro-4a(4H)-dibenzofurancarboxaldehyde(MGK-11),2-(2-ethylhexyl)-3a,4,7,7a-tetrahydro-4,7-methano-1H-isoindole-1,3(2H)dione(MGK-264), dipropyl-2,5-pyridinedicarboxylate (MGK-326) and2-(octylthio)ethanol (MGK-874).

In a particularly preferred embodiment, the topical compositions of theinvention will include permethrin in combination with the isoxazolineactive agent.

An antiparasitic agent that can be combined with the compound of theinvention to form a composition can be a biologically active peptide orprotein including, but not limited to, depsipeptides, which act at theneuromuscular junction by stimulating presynaptic receptors belonging tothe secretin receptor family resulting in the paralysis and death ofparasites. In one embodiment of the depsipeptide, the depsipeptide isemodepside (see Willson et al., Parasitology, January 2003, 126(Pt1):79-86).

In another embodiment, the compositions of the invention may comprise anactive agent from the neonicotinoid class of pesticides. Theneonicotinoids bind and inhibit insect specific nicotinic acetylcholinereceptors. In one embodiment, the neonicotinoid insecticidal agent thatcan be combined with an isoxazoline compound to form a topicalcomposition of the invention is imidacloprid. Imidacloprid is awell-known neonicotinoid active agent and is the key active ingredientin the topical parasiticide products Advantage®, Advantage® II, K9Advantix®, and K9 Advantix® II sold by Bayer Animal Health. Agents ofthis class are described, for example, in U.S. Pat. No. 4,742,060 or inEP 0 892 060.

In another embodiment, the topical compositions of the invention maycomprise nitenpyram, another active agent of the neonicotinoid class ofpesticides. Nitenpyram has the following chemical structure and is theactive ingredient in the oral product CAPSTAR™ Tablets sold by NovartisAnimal Health.

Nitenpyram is active against adult fleas when given daily as an oraltablet. Nitenpyram works by interfering with normal nerve transmissionand leads to the death of the insect. Nitenpyram has a very fast onsetof action against fleas. For example CAPSTAR™ Tablets begin to actagainst fleas in as early as 30 minutes after administration and isindicated for use as often as once a day. However, nitenpyram is onlyknown to be effective when administered orally as a systemicparasiticide, as with CAPSTAR™ Tablets. Therefore, it is surprising andunexpected that the topical compositions of the invention comprising acombination of nitenpyram with an isoxazoline active agent exhibit thevery fast onset of action of nitenpyram because this active agent is notknown to be active when administered topically. The topical compositionsof the invention comprising a combination of a long-lasting isoxazolineactive agent with a very fast acting active agent such as theneonicotinoid active agent nitenpyram provide optimal speed of onset andlong lasting activity against ectoparasites.

Nitenpyram has a very low log octanol-water partition coefficient of−0.64 and a relatively high solubility in water of 840 g/L at 20° C. andpH of 7 (see Supplement to Compendium on Continuing Education for thepracticing veterinarian, vol. 23, no. 3(a), march 2001), indicating thatit is not a likely candidate for topical delivery. Based on the very lowlog p of nitenpyram and the very high water solubility, one of skill inthe art would have a very high level of skepticism that this activeagent could be effectively delivered in a topical composition. Theeffectiveness of topical compositions of the invention that comprisenitenpyram are all the more unexpected in view of the physicochemicalproperties of the compound.

In another preferred embodiment of the invention, topical compositionscomprising at least one isoxazoline compound in combination with an IGRand a neonicotinoid active agent are provided. In still anotherpreferred embodiment, the invention provides topical compositionscomprising an isoxazoline compound of Formula (I) together with an IGRthat mimics juvenile hormone and nitenpyram. In yet another preferredembodiment, the invention provides topical spot-on or pour-oncompositions comprising4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamide(Compound A) in combination with (S)-methoprene or pyriproxyfen andnitenpyram.

In another embodiment, the topical compositions of the invention providetopical spot-on or pour-on compositions that comprise4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamide(Compound A) in combination with nitenpyram, (S)-methoprene orpyriproxyfen and an avermectin or milbemycin compound. In yet anotherembodiment of the invention, topical compositions are provided thatcomprise4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamide(Compound A) in combination with nitenpyram and/or (S)-methoprene orpyriproxyfen and/or an avermectin or milbemycin compound and/orpraziquantel. In this embodiment, the presence of an avermectin ormilbemycin compound and/or praziquantel provides potent activity againstendoparasites in addition to activity against ectoparasites.

In certain embodiments, an insecticidal agent that can be combined withthe compositions of the invention is a semicarbazone, such asmetaflumizone.

In another embodiment, the compositions of the invention mayadvantageously include a combination of isoxazoline compounds known inthe art. These active agents are described in WO 2007/079162, WO2007/075459 and US 2009/0133319, WO 2007/070606 and US 2009/0143410, WO2009/003075, WO 2009/002809, WO 2009/024541, WO 2005/085216 and US2007/0066617 and WO 2008/122375, all of which are incorporated herein byreference in their entirety.

In another embodiment of the invention, nodulisporic acid and itsderivatives (a class of known acaricidal, anthelmintic, anti-parasiticand insecticidal agents) may be added to the compositions of theinvention. These compounds are used to treat or prevent infections inhumans and animals and are described, for example, in U.S. Pat. Nos.5,399,582, 5,962,499, 6,221,894 and 6,399,786, all of which are herebyincorporated by reference in their entirety. The compositions mayinclude one or more of the known nodulisporic acid derivatives in theart, including all stereoisomers, such as those described in the patentscited above.

In another embodiment, anthelmintic compounds of the amino acetonitrileclass (AAD) of compounds such as monepantel (ZOLVIX), and the like, maybe added to the compositions of the invention. These compounds aredescribed, for example, in WO 2004/024704 and U.S. Pat. No. 7,084,280(incorporated by reference); Sager et al., Veterinary Parasitology,2009, 159, 49-54; Kaminsky et al., Nature vol. 452, 13 Mar. 2008,176-181. The compositions of the invention may also includearyloazol-2-yl cyanoethylamino compounds such as those described in U.S.Pat. No. 8,088,801 to Soll et al., which is incorporated herein in itsentirety, and thioamide derivatives of these compounds, as described inU.S. Pat. No. 7,964,621, which is incorporated herein by reference.

The compositions of the invention may also be combined withparaherquamide compounds and derivatives of these compounds, includingderquantel (see Ostlind et al., Research in Veterinary Science, 1990,48, 260-61; and Ostlind et al., Medical and Veterinary Entomology, 1997,11, 407-408). The paraherquamide family of compounds is a known class ofcompounds that include a spirodioxepino indole core with activityagainst certain parasites (see Tet. Lett. 1981, 22, 135; J. Antibiotics1990, 43, 1380, and J. Antibiotics 1991, 44, 492). In addition, thestructurally related marcfortine family of compounds, such asmarcfortines A-C, are also known and may be combined with theformulations of the invention (see J. Chem. Soc.—Chem. Comm. 1980, 601and Tet. Lett. 1981, 22, 1977). Further references to the paraherquamidederivatives can be found, for example, in WO 91/09961, WO 92/22555, WO97/03988, WO 01/076370, WO 09/004432, U.S. Pat. No. 5,703,078 and U.S.Pat. No. 5,750,695, all of which are hereby incorporated by reference intheir entirety.

In general, the additional active agent is included in the compositionin an amount of between about 0.1 μg and about 1000 mg. More typically,the additional active agent may be included in an amount of about 10 μgto about 500 mg, about 1 mg to about 300 mg, about 10 mg to about 200 mgor about 10 mg to about 100 mg.

In other embodiments of the invention, the additional active agent maybe included in the composition to deliver a dose of about 5 μg/kg toabout 50 mg/kg per weight of the animal. In other embodiments, theadditional active agent may be present in an amount sufficient todeliver a dose of about 0.01 mg/kg to about 30 mg/kg, about 0.1 mg/kg toabout 20 mg/kg, or about 0.1 mg/kg to about 10 mg/kg of weight ofanimal. In other embodiments, the additional active agent may be presentin a dose of about 5 μg/kg to about 200 μg/kg or about 0.1 mg/kg toabout 1 mg/kg of weight of animal. In still another embodiment of theinvention, the additional active agent is included in a dose betweenabout 0.5 mg/kg to about 50 mg/kg.

The topical compositions of the invention, which include at least anisoxazoline active agent and a pharmaceutically acceptable carrier thatis suitable for topical application to an animal, have been surprisinglydiscovered to be stable and effective against a broad spectrum ofectoparasites for an extended period of time.

In a preferred embodiment of the inventive compositions, the topicalcomposition will be in the form of a liquid solution or suspension thatcomprises a pharmaceutically acceptable carrier or diluent that issuitable for application to the skin of an animal. Topical, dermal andsubdermal formulations can include emulsions, creams, ointments, gels,pastes, powders, shampoos, pour-on formulations, ready-to-useformulations, spot-on solutions and suspensions.

In a preferred embodiment of the invention, topical compositionssuitable for topical administration to a localized area of an animal areprovided, including compositions in the form of spot-on or pour-oncompositions. In another embodiment, the topical compositions will be inthe form of a spray formulation, an aerosol or a foam formulationsuitable for administration to an animal. In some embodiments, theliquid solution or suspension formulations comprising isoxazoline activeagents will be in a form that can be sprayed on via a metered dose pumpor a metered dose aerosol.

Isoxazoline active agents, such as those of Formula (I), aresystemically active such that the ectoparasite is affected when taking ablood meal from the host. Accordingly, a minimum concentration of thecompounds in the systemic circulation of the animal is required.However, in some situations the isoxazoline active agent may also beactive by contacting the parasite on the surface of the animal. Thus, insome embodiments, topical application of the inventive compositions canallow for the active agents to be delivered and distributed throughoutthe hair coat topically and/or may also provide distribution of theactive agent via the sebaceous glands of the animals. When the compoundis distributed throughout sebaceous glands, the sebaceous glands can actas a reservoir, whereby there can be a long-lasting effect, e.g. atleast one month or longer. For example, Cochet and co-workers reportedthe distribution of fipronil, a 1-arylpyrazole compound, to the stratumcorneum, the viable epidermis and the sebaceous glands and epitheliallayers of beagle dogs after spot-on administration (see Cochet et al.,Eur. J. Drug Metab. Pharmacokinet., 1997, 22(3), 211-216). Using ¹⁴Cradiolabeled drug, the publication demonstrated that fipronil isdisplaced from the point of application and distributed to the wholeskin, where it was persistently detected for up to 56 days aftertreatment.

Topical application of the inventive compositions enables effectivedelivery of the active agent transdermally through the skin into thesystemic circulation at a concentration sufficient to provide excellentefficacy against ectoparasites. In another preferred embodiment, thecompositions of the invention achieve distribution of the active agentboth topically over the hair coat of the animal and also transdermallyinto the blood stream. In this embodiment, the topical compositionsprovide a high level of efficacy at unexpectedly low plasmaconcentrations of the isoxazoline active agent.

The outer layer of the epidermis, the stratum corneum, forms the majorbarrier to both the egress of water and the ingress of xenobiotics intothe circulatory system. It is a unique membrane comprised of dead thinflat cells, corneocytes, which are filled with dense keratin, betweenwhich is a lipid-rich layer comprised of numerous lipid bilayers. Thegeneral consensus is that most xenobiotics pass through the lipid-richlayer between the flat cells. Delivering an active through the skinpresents a significant challenge, given the role of the skin as abarrier for keeping foreign substances out. In order for an activeingredient to pass through the stratum corneum, it must passsequentially across bilayers and therefore cross manyhydrophilic-lipophilic interfaces. Because of the efficient barrier ofthe skin, transdermal delivery is only typically appropriate for potentcompounds that require only a small dosage.

Only materials which have good solubility properties in both oils andwater will be able to effectively pass across the skin with relativeease. One of the major problems in treating the skin or using the skinto deliver a substance into the systemic circulation arises from therequirement that the active has to possess the correct physicochemicalproperties to allow it to reach the site of action or circulation. If itis extremely hydrophilic it will reside on the skin surface. If it isextremely lipophilic it will pass into the lipid-rich layer between thecells and will have difficulty penetrating deeper. Only compounds thatare small, have balanced solubility in oils and water and a log(octanol-water partition coefficient) of ˜2 (log P) will pass throughthe stratum corneum and into the systemic circulation to any significantdegree (see Kenneth B. Sloan (ed.) (1992) Prodrugs: Topical and OcularDrug Delivery, p. 6, Marcel Dekker, New York). Examples include nicotineand nitroglycerin (GTN). However even these are not absorbed to a largedegree. Thus, many compounds are not suitable for transdermal deliverybecause of their inherent physicochemical properties.

It will be understood that the ability of an active agent to bedistributed either topically or transdermally is dependent both on thephysicochemical characteristics of the compound and also on thenon-active excipients of the formulation, which may induce penetrationof the active agent into the skin. While there is no general method todeliver any active agent either topically over the hair coat of ananimal or transdermally to an animal, some techniques for enhancing thepenetration of active agents into the skin of animals are known.Substances termed “permeation enhancers,” are typically used incompositions designed to deliver drugs transdermally to increase theamount of the active that is delivered into the systemic circulation.Permeation enhancers constitute various classes of compounds includingcertain solvents such as dimethylsulfoxide (DMSO), pyrrolidones,ethanol, propylene glycol, ethyl acetate, dimethylacetamide, and othersthat are capable of disrupting the barrier function of the stratumcorneum. Other substances have also been shown to increase the flux ofcertain active agents through the skin. These include lipophiliccompounds such as laurocapram (Azone); fatty acids or alcohols such asoleic acid, oleyl alcohol, linoleic acid and the like; certain fattyacid esters such as isopropyl myristate, methyl noanoate, methyl caprateand others. Mixtures of certain permeation enhancers with propyleneglycol are also known to improve the delivery of certain activeingredients. For example, see Pharmaceutical Skin PenetrationEnhancement edited by Kenneth A. Walters and Jonathan Hadgraft, MarcelDekker, Inc. New York, 1993; ISBN 0-8247-9017-0.

In some embodiments of the invention, the compositions are formulated tocontrol the rate of permeation of the isoxazoline compound in order tomaintain efficacious levels of the active in the plasma for a prolongedperiod of time and significantly extend the duration of efficacy. Thus,in one embodiment, the topical compositions of the invention areformulated with a carrier system that induces the containment of theisoxazoline active agent(s) within the skin to achieve a reservoireffect and controls the permeation rate of the compound into thesystemic circulation over a longer period of time. In this manner, theinvention provides topical compositions that exhibit surprising longlasting efficacy against ectoparasites. It must be noted that thisapproach is only applicable to potent active agents that may achieve thedesired parasiticidal efficacy with low plasma concentrations, sinceless potent compounds would not be able to establish an efficaciousconcentration.

It has been found that the topical compositions of the present inventioncomprising an isoxazoline active agent in a carrier comprising alipophilic solvent or lipophilic solvent system result in superbefficacy against ectoparasites for an extended duration of time.Although not wishing to be bound by theory, it is believed thatnon-active excipients in certain topical formulations of the inventionpromote the containment of the isoxazoline active agent within the skinfor longer periods of time while allowing the active agent to constantlydiffuse into the circulatory system at a rate that provides the requiredconcentration of the active in the blood stream to be efficaciousagainst ectoparasites for a longer period of time. This is contrary tothe approaches used with typical topical formulations that are designedto enhance the passage of active agents through the skin of an animalinto the systemic circulation quickly to obtain the desired biologicaleffect. Thus, in one embodiment the present invention utilizesnon-active excipients that discourage the fast permeation of isoxazolineactive agents into the systemic circulation.

In one embodiment, the invention provides topical compositionscomprising an isoxazoline active agent in a pharmaceutically acceptablecarrier wherein the carrier does not include a compound that enhancesthe permeation of the isoxazoline active agent. In another embodiment,the invention provides topical compositions comprising an isoxazolineactive agent and a pharmaceutically acceptable carrier wherein thecarrier comprises a solvent or solvent system that promotes thecontainment of the isoxazoline active agent in the skin of the animalfor a longer period of time.

In one embodiment of the invention comprising a carrier that extends theduration of efficacy of the topical compositions, the carrier maycomprise a solvent selected from carboxylic acid esters, diesters ofdicarboxylic acids, fatty acid esters or diesters of fatty diacids, or acombination thereof, including, but not limited to, isopropyl palmitate,isostearyl lactate, diisopropyl adipate, dibutyl adipate, diethylsebacate, dibutyl sebacate, octyl palmitate, polyethyleneglycol (PEG)stearate and cetearyl octanoate; oils including, but not limited to,mineral oil, diglycerides, triglycerides, jojoba oil, lecithin andcastor oil, or a combination thereof; long chain aliphatic alcohols suchas isostearyl alcohol and the like; fatty alcohols and their esters,including for example, cetyl alcohol, cetearyl alcohol and the like, ora combination thereof; polyethylene glycols of different molecularweight ranges including, but not limited to, PEG 300, PEG 400, PEG 600and PEG 1000, or a combination thereof; and glycol ethers including, butnot limited to, diethyleneglycol monoethyl ether (Transcutol®), butyldiglycol, propylene glycol monomethyl ether, propylene glycol monoethylether, dipropylene glycol n-butyl ether, ethylene glycol monoethylether, ethylene glycol monomethyl ether and dipropylene glycolmonomethyl ether, or a combination thereof; or a combination of two ormore of these solvents.

Excipients that may also promote the containment of the active agent inthe skin for longer periods of time and may be included in thecompositions of the invention include, but are not limited to, mixedesters of sucrose and carboxylic acids including sucrose acetateisobutyrate (SAM) and the like; low temperature melting waxes,hydrogenated vegetable oils, caprylic/capric glycerides; glycerolesters, including for example, triacetin, glycerol monooleate, glycerolmonolinoleate, glycerol stearate, glyceryl distearate and the like;triglycerides, including for example, caprylic, capric/myristic/stearictriglyceride; thermoreversible polymers, such as Pluronic andpoloxamers, including for example, Lutrol F127 by itself or in mixturewith other poloxamers; or a combination thereof.

In another embodiment of the invention the pharmaceutically acceptablecarrier for the topical compositions comprise a mixture of a diester ofa dicarboxylic acid alone or in combination with one or more ofadditional solvents listed above, and/or an “oily” lipophilic substance,including a liquid or low melting lipophilic active agent such as(S)-methoprene, pyriproxyfen and/or permethrin; and/or a mixed ester ofsucrose and carboxylic acids including a mixed ester of sucrose andacetic and isobutyric acids such as sucrose acetate isobutyrate (SAIB),and/or low melting waxes and/or hard fats.

Although not wishing to be bound by theory, the inclusion of certainlipophilic solvents in the topical compositions of the invention promotethe residence time of the isoxazoline active agent within the skin whileallowing an effective concentration of the active agent to pass slowlyinto the circulatory system to achieve the desired efficacy for longerperiods of time. In a preferred embodiment, the diester of adicarboxylic acid is diethyl sebacate or diisopropyl adipate. In anotherembodiment, the blend of solvents comprising a dicarboxylic acid estercomprises a glycol or polyglycol, or a glycol or polyglycol ether orester including, but not limited to, ethylene glycol (EG), propyleneglycol (PG), liquid polyoxyethylene glycols (PEGs) of various gradesincluding PEG 400, EG or PG monocaprylate, EG or PG caprylate, EG or PGmonolaurate, EG or PG dicaprylate/dicaprate, diethyleneglycol monoethylether (DGME, Transcutol®), butyl diglycol, dipropylene glycol n-butylether, ethyleneglycol monoethyl ether, ethyleneglycol monomethyl ether,dipropylene glycol monomethyl ether, propylene glycol monomethyl ether,propylene glycol monoethyl ether, and the like, or a combinationthereof; an ether including, but not limited to, dimethyl isosorbide; anester or diester including, but not limited to, triacetin, lauryllactate; and other solvents including glycerol formal, or mixturesthereof.

In preferred embodiments, the carrier for the topical compositionscomprises a dialkyl ester of a dicarboxylic acid such as diethylsebacate, diisopropyl sebacate, diisopropyl adipate, dibutyl adipate, ora combination thereof, alone or in combination with solvents selectedfrom:

-   -   a) a propylene glycol (PG) ester including PG monocaprylate, PG        caprylate, PG monolaurate, PG dicaprylate/dicaprate, or a        combination thereof;    -   b) an ether solvent including dimethyl isosorbide, diethylene        glycol monoethyl ether (also known as DGME or Transcutol®), or a        combination thereof;    -   c) a carboxylic acid ester including, but not limited to,        triacetin, lauryl lactate, isopropyl palmitate, diisopropyl        sebacate, or a combination thereof; and    -   d) other “oily” or lipophilic organic solvents including        glycerol formal and the like.

In some embodiments, the amount the additional solvents combined withthe carboxylic acid ester or diester of a dicarboxylic acid are presentin an amount of at least about 1% (v/v), at least about 5% (v/v), atleast about 9.0% (v/v), at least about 13% (v/v), at least about 17%(v/v) or at least about 20% (v/v). Preferably the additional solventswill be in an amount of at least about 9% (v/v).

In other embodiments, the additional solvents will be present in anamount of about 5-70% (v/v), about 10-60% (v/v), about 10-50% (v/v),about 15-60% (v/v) or about 15-50% (v/v). In preferred embodiments, theadditional solvents will be present in an amount of about 20-70% (v/v),about 20-60% (v/v), about 20-50% (v/v) or about 25-50% (v/v).

The pharmaceutically acceptable carrier may include suitable carriers ordiluents commonly used in the formulation art including aqueous ororganic solvents or mixtures of solvents. These organic solvents may befound, for example, in Remington Pharmaceutical Sciences, 21^(st)Edition (2005). Other solvents and/or additives that may be used in thetopical compositions include, but are not limited to, PEG ethers and PEGesters including, but not limited to, PEG esters of carboxylic acids anddicarboxylic acids and PEG esters of fatty acids, glycerol estersincluding triacetin, caprylic/capric triglycerides (Miglyol 812®) andthe like; glycerol ethers including glycerol formal; propylene glycoldicaprylate/dicaprate (Miglyol 840, lauryl lactate, triacetin,diisopropyl adipate (DIPA, also known as CERAPHYL 230), diisobutyladipate, dimethyl isosorbide (DMI), acetyltributyl citrate, oleic acid;carboxylic acid esters including esters of diacids, ketones includingacetone, methylisobutyl ketone (MIK), methyl ethyl ketone, and the like;acetonitrile, C₁-C₁₂ alcohols including benzyl alcohol, methanol, ethylalcohol, isopropanol, and butanol; aromatic ethers such as anisole;amides including dimethylacetamide, monomethylacetamide anddimethylformamide; dimethyl sulfoxide (DMSO), ethylene glycol, propyleneglycol, a glycol carbonate including, but not limited to, propylenecarbonate and, butylene carbonate; 2-pyrrolidone, N-methylpyrrolidone,C₁-C₁₂ alkyl esters of carboxylic acids including butyl or octyl acetateand benzyl acetate; C₁-C₁₂ alkyl esters of dicarboxylic acids; arylesters including benzyl benzoate, ethyl benzoate and the like; anddiethyl phthalate, or a mixture of at least two of these solvents.

However, in one embodiment, the invention provides topical compositionscomprising at least one isoxazoline active agent, optionally incombination with one or more additional active agents, in apharmaceutically acceptable carrier, wherein the carrier does notcomprise glycofurol. In another embodiment, the pharmaceuticallyacceptable carrier of the topical compositions does not comprise abinary mixture of propylene glycol and glycerol formal.

As vehicle or diluent, mention may also be made of plant oils such as,but not limited to soybean oil, groundnut oil, castor oil, corn oil,cotton oil, olive oil, grape seed oil, sunflower oil, etc.; mineral oilssuch as, but not limited to, petrolatum, paraffin, silicone, etc.;aliphatic or cyclic hydrocarbons including limonene or alternatively,for example, medium-chain (such as C₈ to C₁₂) triglycerides, or mixturesthereof.

In one embodiment, solvents and/or additives that control the permeationrate of the active may be added to a composition comprising one of theformulation carriers described herein, including carriers comprising adialkyl ester of a dicarboxylic acid such as diethyl sebacate or thelike. In another embodiment, solvents and/or additives that control thepermeation rate of the active may be added to carriers comprising othersolvents described herein or may be used alone in the composition.

It will be appreciated by those skilled in the art that the skin ofdifferent animals will be different in nature and may be more or lesspermeable to the isoxazoline active agent. For example, the retainmentof the isoxazoline active agent on the skin of a cat may be moredifficult than dogs. Accordingly, in some situations with certainanimals the topical compositions of the invention will utilize solventsthat enhance the permeation of the isoxazoline active agent through theskin of the animal rather than solvents and excipients that retain theactive agent on the skin of the animal for longer periods of time. Thus,in another embodiment of the invention, topical compositions areprovided that include solvents that enhance the permeation ofisoxazoline active agents through the skin of the animal. These solventsprovide a greater proportion of the active agent through the skin andthereby improve the efficacy and duration of time. In this embodiment,the permeation enhancing solvent permits a greater proportion of theisoxazoline active agent through the skin into the systemic circulation.It will be appreciated by those of skill in the art that this effectallows a greater level of efficacy at lower doses of the active.Selected solvents that enhance the permeation of the isoxazoline activeagent include, but are not limited to, dimethyl isosorbide; and glycolethers including, but not limited to, diethyleneglycol monoethyl ether(DGME, Transcutol®), butyl diglycol, dipropylene glycol n-butyl ether,ethyleneglycol monoethyl ether, ethyleneglycol monomethyl ether,dipropylene glycol monomethyl ether, propylene glycol monomethyl ether,propylene glycol monoethyl ether, and the like. Other solvents thatenhance the permeation of the isoxazoline active agent described belowmay also be used in the compositions.

In one embodiment of the invention, the pharmaceutically acceptablecarrier of the formulation may comprise C₈-C₂₀ long-chain aliphaticalcohols or esters thereof. In another embodiment, the carrier comprisesC₁-C₁₂ alcohols or esters thereof, C₁-C₄ alcohols or esters thereof orC₃-C₈ alcohols or esters thereof. In some embodiments, the esters formedwith the alcohol include esters of C₁-C₁₂ carboxylic acids or diacids,or esters of C₆-C₁₆ carboxylic acids or diacids. Esters include, but arenot limited to, acetates such as ethyl acetate and the like; and estersof C₁-C₁₂ alcohols and a dicarboxylic acid or a hydroxy-substitutedcarboxylic acids.

In another embodiment, the pharmaceutically acceptable carrier comprisesC₄-C₂₂ fatty acids or esters thereof, including esters with C₆-C₂₀ longchain alcohols, C₁-C₁₂ alcohols, C₁-C₄ alcohols or C₃-C₈ alcohols;C₁₀-C₁₈ saturated fatty acids or esters thereof, including esters withC₆-C₂₀ long chain alcohols, C₁-C₁₂ alcohols, C₁-C₄ alcohols or C₃-C₈alcohols; C₁₀-C₁₈ unsaturated fatty acids or esters thereof, includingesters with C₆-C₂₀ long chain alcohols, C₁-C₁₂ alcohols, C₁-C₄ alcoholsor C₃-C₈ alcohols; monoesters or diesters of C₆-C₁₆ aliphatic carboxylicacids and carboxylic diacids, including esters with C₆-C₂₀ long chainalcohols, C₁-C₁₂ alcohols, C₁-C₄ alcohols or C₃-C₈ alcohols, or mixturesthereof. In other embodiments, the carrier may include C₁-C₁₀, C₁-C₈ orC₁-C₆ alcohols or esters thereof.

In another embodiment, the compositions of the invention comprisearomatic alcohols or esters thereof. In one preferred embodiment, thetopical compositions of the invention may include benzyl alcohol as asolvent.

In another embodiment, preferred solvents include C₁-C₁₂ alkyl esters ofcarboxylic acids such as butyl acetate, octyl acetate, lauryl lactate orisopropyl palmitate, and C₁-C₁₂ alkyl esters of dicarboxylic acids,including diisopropyl adipate, diethyl sebacate and diisopropylsebacate. In other embodiments, the carrier may include C₁-C₁₀, C₁-C₈ orC₁-C₆ alkyl esters of carboxylic acids or C₁-C₁₀, C₁-C₈ or C₁-C₆ alkyldiesters or dicarboxylic acids. In one embodiment, the carboxylic acidor dicarboxylic acid is a C₄-C₂₂ fatty acid or dicarboxylic acid. Inanother embodiment, the carboxylic acid or dicarboxylic acid is a C₁-C₁₂carboxylic acid or dicarboxylic acid. In other embodiments, thecarboxylic acid or dicarboxylic acid is a C₁-C₁₀, C₁-C₈ or C₁-C₆carboxylic acid or dicarboxylic acid.

In some preferred embodiments, the carrier or diluent include aderivative of glycerol including, but not limited to, glycerolmonoesters (e.g. monoglycerides), glycerol diesters (e.g. diglycerides),glycerol triesters (e.g. triglycerides such as triacetin), or glycerolformal, or mixtures thereof. Glycerol formal is a mixture of5-hydroxy-1,3-dioxane and 4-hydroxymethyl-1,3-dioxolane (approximately60:40), which are cyclic ether compounds derived from glycerol andhaving 2 oxygen atoms in the ring structure and substituted by alcoholgroup. Glycerol Formal is a low odor and low toxic solvent for a widevariety of applications in pharmaceutical and cosmetics industryincluding anti-parasite veterinary formulations.

In another embodiment of the invention, the organic solvents maycomprise diisopropyl adipate, dipropylene glycol monomethyl ether,propylene glycol monomethyl ether, 2-pyrrolidone, N-methylpyrrolidone,diethylene glycol monoethyl ether, triacetin, butyl acetate, benzylalcohol, octyl acetate, propylene carbonate, oleic acid, or a mixture ofat least two of these solvents.

In some embodiments of the invention, the carrier comprises dimethylisosorbide. Dimethyl isosorbide (DMI) is a high purity solvent andcarrier which offers a safe, effective delivery enhancement mechanismfor active ingredients in personal care products and pharmaceuticalformulations. In addition dimethyl isosorbide is sometimes used as anepidermal penetration enhancer to provide enhanced penetration of activeagents to the epidermis. It may also provide delivery of active agentsinto the skin while avoiding crystallization of the active agent, whichwill severely limit the effectiveness of the formulation. DimethylIsosorbide is soluble in a variety of ingredients including water,cottonseed oil, isopropanol, isopropyl myristate, propylene glycol,polysorbate 20, and polysorbate 80.

In other embodiments, the carrier or diluent may comprise a glycolderivative including, but not limited to, propylene glycol, ethyleneglycol; glycol ethers and polyglycol ethers including, but not limitedto, butyl diglycol, propylene glycol monomethyl ether, propylene glycolmonoethyl ether, dipropylene glycol n-butyl ether, ethylene glycolmonoethyl ether, ethylene glycol monomethyl ether, dipropylene glycolmonomethyl ether, and diethylene glycol monoethyl ether (DGME orTranscutol®).

In a preferred embodiment, the topical compositions of the inventioncomprising isoxazoline active agent(s) are dissolved in apharmaceutically acceptable carrier comprising one or more solvents. Insome embodiments of the invention solvents include, but are not limitedto, dimethyl isosorbide (DMI), glycerol formal (methylidinoglycerol orglycerin formal), triacetin, liquid polyethyleneglycols including PEG400, diisopropyl adipate (DIPA), isopropyl palmitate, silicone fluidincluding SILICONE FLUID 200 and Silicone Fluid 1 cst and/or SiliconeFluid 2cst and the like; propylene glycol (or other aliphatic dihydricalcohols), benzyl alcohol, propylene glycol esters including propyleneglycol dicaprylate/dicaprate, propylene carbonate, propylene glycolmonocaprylate, propylene glycol dicaprylate, propylene glycolmonolaurate and propylene glycol dilaurate; alkyl esters of dicarboxylicacids including diethyl sebacate (DES), diisopropyl sebacate; and estersor diesters of fatty acid, or combinations thereof.

In an embodiment of the invention, the compositions of the invention mayinclude surfactants. The surfactants may be anionic, cationic, non-ionicor amphoteric surfactants. Anionic surfactants include, but are notlimited to, alkaline stearates; calcium stearate; triethanolaminestearate; sodium abietate; alkyl sulfates; sodiumdodecylbenzenesulphonate, sodium dioctylsulphosuccinate; fatty acids,and the like. Examples of cationic surfactant include, but are notlimited to, water-soluble quaternary ammonium salts of formula;cetyltrimethylammonium bromide and octadecylamine hydrochloride.Non-ionic surfactants that may be used in the compositions include, butare not limited to, polyoxyethylenated (PEGylated) esters including, butnot limited to, sorbitan esters and fatty acid esters; polyethyleneglycol stearate, polyoxyethylenated derivatives of castor oil,polyglycerol esters, polyoxyethylenated fatty alcohols,polyoxyethylenated fatty acids, and copolymers of ethylene oxide andpropylene oxide including, but not limited to, block co-polymers ofethylene oxide and propylene oxide such as poloxamers and the like (e.g.Lutrol® F grades and L grades from BASF including Lutrol® F68, F87, F108 and F 127 and others), and the like. Further example of surfactantsinclude, but are not limited to, CAPRYOL™ 90 (propylene glycolmonocaprylate), CAPRYOL™ PGMC (propylene glycol monocaprylate) which areoily liquids having an HLB (hydrophilic-lipophilic balance) of 6 and 5,respectively. Topically they can be used as a co-surfactant inmicroemulsions and as a solubilizer/penetration enhancer.

As used herein, HLB values have the following general meanings:compounds with a HLB value of <10 tend to be lipid soluble (waterinsoluble) and solvents with a HLB >10 tend to be water soluble.Surfactants having HLB between 4 and 8 are typically useful asanti-foaming agents. Surfactants having HLB from 7 to 11 may be usefulas W/O (water in oil) emulsifiers. HLB of 12 to 16 typically indicates asurfactant may be useful in oil in water emulsions, and HLB of 11 to 14is indicative of a wetting agent. HLB of 12 to 15 is typical ofdetergents, and HLB of 16 to 20 indicates a solubilizer or hydrotrope.There is significant an overlap of ranges/uses, and a skilled personwell understands that the HLB value alone cannot be used to predictwhether a particular surfactant will serve a specific purpose (e.g.anti-foaming agent, emulsifier, wetting agent, solubilizer, hydrotrope).Therefore, in general, determination of a suitable system of solvent,active agent, surfactant(s) and other excipients necessarily involvesnon-routine experimentation and inventive effort.

The compositions may also include surfactants such as oleoylmacrogolglycerides (polyoxylglycerides, for example, LABRAFIL® M1944CSand LABRAFIL® M2125CS both having an HLB of 4). These compounds may alsobe used, for example, as oily phase for emulsions, microemulsions, andas penetration enhancers.

In another embodiment, the polyoxylglycerides may includepolyethyleneglycol caprylic/caprylic glycerides such as LABRASOL® (HLBof 14. Topically it is used as a surfactant in microemulsions, and canalso act as a solubility/penetration enhancer in topical formulations.

In another embodiment the surfactant is LAUROGLYCOL™90 (propylene glycolmonolaurate) having an HLB of 5. It is a co-surfactant formicroemulsions in topical formulations and can also act as asolubilizer/penetration enhancer in topical formulations. In someembodiments, the surfactant is PLUROL® OLEIQUE CC497 (polyglyceryloleate), having an HLB of 6.

Certain solvents suitable for topical formulations may be characterizedas having good spreading properties while other solvents for topicalformulations may be characterized by an ability to enhance permeation ofactive agents through the skin barrier into the systemic circulation(see for example, Pharmaceutical Skin Penetration Enhancement, edited byJonathan Hadgraft and Kenneth A. Walters, Marcel Dekker, Inc. New York1993). In some instances, solvents suitable for topical formulations mayinclude both good spreading and good permeation characteristics. DIPA,diisopropyl sebacate, DES and Miglyol 840 have both good spreading andpermeation characteristics. Transcutol, DMI, lauryl lactate, propyleneglycol caprylate, propylene glycol monocaprylate and propylene glycolmonolaurate have good permeation enhancing properties but are notconsidered to have particularly good spreading properties. In certainembodiments of the invention, the compositions will comprise mixtures ofsolvents that will enhance the spreading ability and/or the permeationenhancing ability of the composition.

In some embodiments of the invention, formulations are provided whereinthe carrier comprises solvents that exhibit both good spreading andpermeation characteristics including, but not limited to, DIPA,diisopropyl sebacate, DES and Miglyol® 840. In other embodiments, theinvention provides formulations wherein the carrier comprises solventsthat exhibit good spreading characteristics. In still another embodimentof the invention, formulations are provided wherein the carrier vehiclecomprises solvents that enhance the permeation of the active agentthrough the skin into the systemic circulation.

In one embodiment, the composition exhibits long lasting efficacy andprovides protection against parasites in domestic animals for at leastone month. In one embodiment, the composition comprises a carrier thatincludes a solvent system comprised of a carboxylic acid alkyl ester ordiester of a dicarboxylic acid. In another embodiment, the compositioncomprises a blend of solvents comprising a carboxylic acid alkyl esteror a diester of a dicarboxylic acid.

In another embodiment, the compositions of the invention exhibit verylong lasting efficacy of at least 90% against fleas and/or ticks thatfor a period of at least 1 month, at least 2 months, at least 3 months,at least 4 months, at least 5 months, or at least 6 months against fleasand/or ticks. In one embodiment, the long-lasting composition comprisesa carrier that includes a carboxylic acid alkyl ester or a diester of adicarboxylic acid, including diethyl sebacate and diisopropyl adipate.In another embodiment, the long-lasting composition comprises acarboxylic acid alkyl ester or a diester of a dicarboxylic acid combinedwith an co-solvent including, but not limited to, a propylene glycol(PG) ester including PG monocaprylate, PG caprylate, PG monolaurate andPG dicaprylate/dicaprate; diethyleneglycol monoethyl ether (DGME,Transcutol®), mineral oil, triglycerides, diglycerides, isostearylalcohol, isostearyl lactate, dibutyl adipate, dibutyl sebacate;polyethylene glycols (PEGs) including PEG 400, PEG stearate; lecithin,castor oil and castor oil derivatives, film formers, myristyl myristate,dimethiconol argenine, sucrose acetyl isobutyrate, and the like, or acombination thereof.

In still another embodiment, the long-lasting compositions that providean efficacy of at least 90% against fleas and/or ticks for at least 1month, at least 2 months, at least 3 months, at least 4 months, at least5 months, or at least 6 months, comprise a carrier vehicle that includesdimethyl isosorbide. As mentioned above, DMI is a known permeationenhancer, and use of this solvent in some topical formulations of theinvention results in increased delivery of the active agent into thesystemic circulation. In particular, it was found that the use of DMI intopical formulations for cats resulted in surprising efficacy for up toat least 3 months, at least 4 months, at least 5 months or even at least6 months, against fleas.

In yet another embodiment, the long-lasting compositions that provide anefficacy of at least 90% against fleas and/or ticks comprises a glycolether including, but not limited to, diethyleneglycol monoethyl ether(DGME, Transcutol®), butyl diglycol, dipropylene glycol n-butyl ether,ethyleneglycol monoethyl ether, ethyleneglycol monomethyl ether,dipropylene glycol monomethyl ether, propylene glycol monomethyl ether,propylene glycol monoethyl ether, and the like.

As discussed above, isoxazoline active agents such as those of Formula(I), and in particular4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamide(Compound A), are systemically active such that the ectoparasite isaffected when taking a blood meal from the host. Accordingly, a minimumconcentration of the compounds in the systemic circulation of the animalis required to effectively control ectoparasites such as ticks andfleas. It was surprisingly found that the topical formulations of theinvention comprising an isoxazoline active agent provide excellentefficacy against fleas and ticks at unexpectedly very low plasmaconcentrations. In some embodiments, the topical compositions of theinvention comprising selected solvents and excipients, including dialkylesters of dicarboxylic acids such as diethyl sebacate and the like,result in constant low levels of the active agent over a prolongedperiod of time. In some embodiments, the concentration of the activeagent in the plasma that is sufficient to obtain at least 90% efficacyagainst fleas and/or ticks is less than or equal to about 200 ng/mL orless than or equal to about 150 ng/mL. In other preferred embodiments,the concentration of the isoxazoline active agent in the plasma requiredto attain 90% efficacy against fleas and/or ticks is less than or equalto about 100 ng/mL, less than or equal to about 75 ng/mL or even lessthan or equal to about 50 ng/mL. In other embodiments of the invention,the concentration of the isoxazoline active agent in the plasma requiredto attain 90% efficacy against fleas and ticks is about 75-100 ng/mL,about 50-75 ng/mL or about 30-50 ng/mL.

Furthermore, it was also surprisingly found that the concentration ofthe isoxazoline active agent (Compound A) in the plasma required toattain an efficacy of at least 90% against certain tick species comparedto an untreated control or a control group treated with a placebo wassignificantly less than the plasma concentration required to attain 90%efficacy from another mode of administration that achieves high systemicexposure, such as oral or injectable administration. It was found thatthe concentration of the isoxazoline active agent required to achieve90% efficacy against the tick species A. americanum, D. variabilis andR. sanguineus in dogs was about 42%, 36% and 32% lower than theconcentration required from oral administration (see Example 13). Thiseffect is surprising and unexpected for an active agent that is activeagainst ectoparasites through ingestion of a blood meal, as with theisoxazoline class of compounds. Although not wanting to be bound bytheory, the lower plasma concentration required to achieve 90% efficacyfrom the topical compositions of the invention may indicate that thecompositions provide protection against ectoparasites by acting bothtopically on the surface of the animal and systemically. The improvedefficacy of the topical compositions of the invention against these tickspecies at significantly lower plasma concentrations may allow for alonger duration of efficacy based on the ability of the non-activeexcipients in the inventive compositions to provide a slow delivery ofeffective amounts of isoxazoline active agents into the blood streamfrom the site of application.

As mentioned above, it was surprisingly discovered that the addition ofcertain other active agents with the isoxazoline active agent in thetopical compositions of the invention significantly enhanced the longlasting efficacy of the compositions. For example, inclusion of an IGRactive agent such as the juvenile hormone mimic methoprene in thetopical compositions resulted in significantly longer lasting efficacyagainst ectoparasites. Thus, in one preferred embodiment the inventionprovides very long lasting topical compositions comprising at least oneisoxazoline active agent in combination with an insect growth regulator(IGR) active agent. Preferably, the IGR will be a juvenile hormone mimicincluding azadirachtin, diofenolan, fenoxycarb, hydroprene, kinoprene,pyriproxyfen, tetrahydroazadirachtin or4-chloro-2-(2-chloro-2-methylpropyl)-5-(6-iodo-3-pyridylmethoxy)pyridizin-3(2H)-one,as discussed herein. More preferably, the IGR will be methoprene orpyriproxyfen. As described in the non-limiting examples, the inclusionof the IGR (S)-methoprene with the isoxazoline active agent resulted insignificantly longer lasting efficacy. This effect is surprising andunexpected, as methoprene is not an adulticide (see Examples 1-3).

In another embodiment of the invention, it was surprisingly discoveredthat inclusion of a neonicotinoid active agent such as nitenpyram in thetopical compositions of the invention significantly increased the speedof kill of the compositions against fleas. Thus, a topical compositioncomprising nitenpyram in combination with an isoxazoline active agentand optionally an IGR active agent and/or other oily active agentsand/or active agents with low melting points such as permethrin, provideefficacy of at least 90% against fleas as early as 12 hours afteradministration of the topical formulation and also provide long lastingefficacy. In yet other embodiments of the invention, the topicalcompositions provide efficacy of at least 90% against fleas as early as9 hours or 6 hours after administration. In one embodiment of theinvention, the compositions comprising a combination of nitenpyram andan isoxazoline active agent provide efficacy of at least 90% againstfleas as early as 12 hours, 9 hours or 6 hours after treatment and anefficacy of at least 90% for a period of at least 1 month. In otherembodiments, the compositions comprising a combination of nitenpyram andan isoxazoline active agent provide efficacy of at least 90% as early as12 hours, 9 hours or 6 hours after treatment and an efficacy of at least90% for a period of at least 2 months or at least 3 months, or longer.The fast acting and long lasting protection provided by a combination ofthe neonicotinoid nitenpyram and an isoxazoline active agent is verysurprising and unexpected because nitenpyram is only known to beeffective when administered orally, as with the product CAPSTAR™Tablets.

In other embodiments, the compositions of the invention may be in theform of oil-in-water or water-in-oil emulsions. In some embodiments theoily phase may be a vegetable oil, for example, olive oil or arachisoil, or a mineral oil, for example, liquid paraffin or mixtures ofthese. Suitable emulsifying agents include naturally-occurringphosphatides, for example, soy bean, lecithin, and esters or partialesters derived from fatty acids and hexitol anhydrides, for example,sorbitan mono oleate, and condensation products of the said partialesters with ethylene oxide, for example, polyoxyethylene sorbitan monooleate, and the like. In some embodiments, the emulsions may alsocontain preservatives.

In another embodiment of the formulation, the composition of theinvention is in the form of a microemulsion. Microemulsions are wellsuited as the liquid carrier vehicle. Microemulsions are typicallyquaternary systems comprising an aqueous phase, an oily phase, asurfactant and a co-surfactant. They are usually translucent andisotropic liquids. Microemulsions are composed of stable dispersions ofmicrodroplets of the aqueous phase in the oily phase or conversely ofmicrodroplets of the oily phase in the aqueous phase. The size of thesemicrodroplets is typically less than 200 nm (1000 to 100,000 nm foremulsions). The interfacial film is composed of an alternation ofsurface-active (SA) and co-surface-active (Co-SA) molecules which, bylowering the interfacial tension, allows the microemulsion to be formedspontaneously.

In one embodiment of the oily phase, the oily phase can be formed frommineral or vegetable oils, from unsaturated polyglycosylated glyceridesor from triglycerides, or alternatively from mixtures of such compounds.In one embodiment of the oily phase, the oily phase comprises oftriglycerides. In another embodiment of the oily phase, thetriglycerides are medium-chain triglycerides, for example C₈-C₁₀caprylic/capric triglyceride. In another embodiment, the oily phase willrepresent a % v/v range selected from the group consisting of about 1 toabout 20%; about 2 to about 15%; about 7 to about 10%; and about 8 toabout 9% v/v of the microemulsion.

The aqueous phase typically includes, for example water or glycolderivatives, such as propylene glycol, glycol ethers, polyethyleneglycols or glycerol. In one embodiment of the glycol derivatives, theglycol is selected from the group consisting of propylene glycol,diethylene glycol monoethyl ether, dipropylene glycol monoethyl etherand mixtures thereof. Generally, the aqueous phase will represent aproportion from about 1 to about 10% v/v or about 1 to about 4% v/v inthe microemulsion.

Surfactants for the microemulsion typically include diethylene glycolmonoethyl ether, dipropyelene glycol monomethyl ether, polyglycolyzedC₈-C₁₀ glycerides or polyglyceryl-6 dioleate, or a combination of thesesurfactants. In addition to these surfactants, the co-surfactantsinclude short-chain alcohols, such as ethanol and propanol.Additionally, poloxamers and Pluronic F127 can be used as surfactants.

Some compounds are common to the three components discussed above, i.e.,aqueous phase, surfactant and co-surfactant. However, it is well withinthe skill level of the practitioner to use different compounds for eachcomponent of the same formulation.

Oily suspensions may be formulated by suspending the active ingredientin a vegetable oil, for example, arachis oil, olive oil, sesame oil orcoconut oil, or in mineral oil such as liquid paraffin, and the like.The oily suspensions may contain a thickening agent, for example,beeswax, hard paraffin or cetyl alcohol, and the like. Thesecompositions may be preserved by the addition of an anti-oxidant such asascorbic acid or other known preservatives.

Aqueous suspensions may contain the active agents in admixture withexcipients suitable for the manufacture of aqueous suspensions. Suchexcipients include suspending agents, for example, sodiumcarboxymethylcellulose, methylcellulose, hydroxy-propylmethylcellulose,sodium alginate, polvinylpyrrolidone, gum tragacanth and gum acacia;dispersing or wetting agents may be a naturally-occurring phosphatide,for example lecithin, or condensation products of an alkylene oxide withfatty acids, for example polyoxyethylene stearate, or condensationproducts of ethylene oxide with long chain aliphatic alcohols, forexample, heptadecaethyleneoxycetanol, or condensation products ofethylene oxide with partial esters derived from fatty acids and ahexitol such as polyoxyethylene sorbitol mono-oleate, or condensationproducts of ethylene oxide, with partial esters derived from fatty acidsand hexitol anhydrides, for example polyethylene sorbitan mono-oleate.The aqueous suspensions may also contain one or more preservatives, forexample ethyl, or n-propyl, p-hydroxybenzoate, one or more coloringagents.

Colorants may be added to the inventive formulations. Colorantscontemplated by the present invention are those commonly known in theart. Specific colorants include, for example, dyes, FD&C Blue #1Aluminum Lake, caramel, colorant based upon iron oxide or a mixture ofany of the foregoing. Especially preferred are organic dyes and titaniumdioxide. Preferred ranges include from about 0.01% to about 2% (w/v),more preferably from about 0.01% to about 0.5% (w/v).

In preferred embodiment, the compositions of the invention are in theform of a spot-on formulation that is applied to a localized area on ananimal, rather than the entire coat of the animal or a large portion ofthe animal's coat. In one embodiment of a localized region, the locationis between the shoulders. The spot-on formulation according to thepresent invention provide long-lasting and broad-spectrum efficacyagainst ectoparasites and/or endoparasites when the solution is appliedto the animal. The spot-on formulations provide for topicaladministration of a concentrated solution, suspension, microemulsion oremulsion for intermittent application to localized area on the animal,generally between the two shoulders.

Spot-on formulations are well known techniques for topically deliveringcertain antiparasitic agents to a limited area of the host. However, notall compounds are suited for formulation in spot-on formulations becausethe physicochemical characteristics of the active agent may not alloweffective distribution of the compound topically or transdermally. U.S.Pat. Nos. 5,045,536, 6,395,765; 6,096,329; 7,262,214; 6,426,333;6,482,425; 6,962,713; 6,998,131; and 7,531,186, all incorporated hereinby reference, describe spot-on formulations. WO 01/957715, alsoincorporated herein by reference, describes a method for controllingectoparasites in small rodents as well as interrupting or preventing thediseases caused by arthropods in small rodents, which comprise applyingtopical formulations, such as spot-on compositions, to the skin, or hairof the rodents.

Spot-on formulations may be prepared by dissolving the activeingredients into the pharmaceutically or veterinary acceptable vehicle.Alternatively, the spot-on formulation can be prepared by encapsulationof the active ingredients to leave a film of the therapeutic agent onthe surface of the animal. These formulations will vary with regard tothe weight of the therapeutic agent in the combination depending on thespecies of host animal to be treated, the severity and type of infectionand the body weight of the host.

For spot-on formulations, the pharmaceutically acceptable carrier may bea liquid carrier vehicle as described herein, and other carriersdescribed in the art, for example in U.S. Pat. No. 6,395,765 and otherpatents listed in the previous paragraph. In some embodiments, theliquid carrier vehicle can optionally contain a crystallizationinhibitor such as the crystallization inhibitors described below, ormixtures thereof, to inhibit the formation of crystals or precipitate ofthe active components.

The veterinarily acceptable carrier will generally comprise a diluent orvehicle in which the active agents are soluble. It will be apparent tothose of skill in the art that the carrier or diluent of the topicalcompositions must be able to deliver the active agents to the targetedlocation without the active agents precipitating from solution orforming crystals. In some embodiments, the carrier or diluent of thecompositions will be suitable to avoid precipitation or crystallizationof the active agents. In other embodiments, the compositions may includea crystallization inhibitor component in addition to the carrier ordiluent.

Crystallization inhibitors which are useful for the invention includebut are not limited to:

(a) polyvinylpyrrolidone, polyvinyl alcohols, copolymers of vinylacetate and of vinylpyrrolidone, 2-pyrrolidone includingN-methylpyrrolidone, dimethylsulfoxide, polyethylene glycols,co-polymers of polyoxyethylene and polyoxypropylene, benzyl alcohol,mannitol, glycerol, sorbitol or polyoxyethylenated esters of sorbitan;lecithin or sodium carboxymethylcellulose; or acrylic derivatives, suchas polymers derived from acrylic monomers including polyacrylates orpolymethacrylates; and, a solvent as described herein that inhibits thecrystallization of the active agent, and similar compounds;

(b) anionic surfactants, such as alkaline stearates (e.g. sodium,potassium or ammonium stearate); calcium stearate or triethanolaminestearate; sodium abietate; alkyl sulfates, which include but are notlimited to sodium lauryl sulfate and sodium cetyl sulfate; sodiumdodecylbenzenesulfonate or sodium dioctyl sulphosuccinate; or fattyacids (e.g. coconut oil);

(c) cationic surfactants, such as water-soluble quaternary ammoniumsalts of formula N⁺R′R″R′″R″″Y⁻, in which the R radicals are identicalor different optionally hydroxylated hydrocarbon radicals and Y⁻ is ananion of a strong acid, such as halide, sulfate and sulfonate anions;cetyltrimethylammonium bromide is one of the cationic surfactants whichcan be used;

(d) amine salts of formula N⁺HR′R″R′″ Y⁻, in which the R radicals areidentical or different optionally hydroxylated hydrocarbon radicals andY⁻ is the anion of a mineral or organic acid; octadecylaminehydrochloride is one of the cationic surfactants which can be used;

(e) non-ionic surfactants, such as optionally polyoxyethylenated estersof sorbitan, e.g. Polysorbate 80, or polyoxyethylenated alkyl ethers;polyethylene glycol stearate, polyoxyethylenated derivatives of castoroil including hydrogenated castor oil and its derivatives, polyglycerolesters, polyoxyethylenated fatty alcohols, polyoxyethylenated fattyacids or copolymers of ethylene oxide and of propylene oxide;

(f) amphoteric surfactants, such as substituted lauryl compounds ofbetaine; or

(g) a mixture of at least two of the compounds listed in (a)-(f) above.

In one embodiment of the crystallization inhibitor, a crystallizationinhibitor pair will be used. Such pairs include, for example, thecombination of a film-forming agent of polymeric type and of asurface-active agent. Other crystallization inhibitor pairs include apolyethylene glycol and a non-ionic surfactant. Additionalcrystallization pairs including other mixtures are also contemplated.These agents can be selected from the compounds mentioned above ascrystallization inhibitor.

In one embodiment of the film-forming agent, the agents are of thepolymeric type which include but are not limited to the various gradesof polyvinylpyrrolidone, polyvinyl alcohols, polyethylene glycols andcopolymers of vinyl acetate and of vinylpyrrolidone.

In one embodiment of the surface-active agents, the agents include butare not limited to those made of non-ionic surfactants. In anotherembodiment of the surface active agents, the agent is apolyoxyethylenated ester of sorbitan. In yet another embodiment of thesurface-active agent, the agents include the various grades ofpolysorbate, for example Polysorbate 80 and polyoxyethylenatedderivatives of castor oil including hydrogenated castor oil derivatives.

In another embodiment of the invention, the film-forming agent and thesurface-active agent can be incorporated in similar or identical amountswithin the limit of the total amounts of crystallization inhibitormentioned above.

In some embodiments, the crystallization inhibitor can be present in aproportion of about 1 to about 30% (w/v). Typically, the crystallizationinhibitor may be present in a proportion of about 1% to about 20% (w/v),about 1% to about 10% (w/v), or about 5% to about 15% (w/v). Acceptableinhibitors are those whose addition to the formulation inhibits theformation of crystals of the active agents when the formulation isapplied. In some embodiments, formulations may include compounds thatfunction as crystallization inhibitors other than those listed herein.In these embodiments, the suitability of a crystallization inhibitor maybe determined by testing if it will sufficiently inhibit the formationof crystals so that a sample containing 10% (w/v) of the isoxazolineactive agent in a solvent as described above with 10% (w/v) of thecrystallization inhibitor will result in less than 20, preferably lessthan 10 crystals when placed on a glass slide at 20° C. for 24 hours.

In some embodiments of the invention, an emollient and/or spreadingand/or film-forming agent may be added to the topical compositions ofthe invention. Emollients, spreading agents and film forming agents arewell known in the art. In various embodiments, the emollients, spreadingagents and film forming agents that may be used in the topicalcompositions include the components listed in (a) to (g) above,including polymer derivatives such as polyvinylpyrrolidone, polyvinylalcohols and copolymers of vinyl acetate and vinylpyrrolidone; anionicsurfactants; cationic surfactants; non-ionic surfactants; amphotericsurfactants; amine salts, and combinations thereof. In one embodiment,the emollient is used in a proportion of from about 0.1 to about 10%, orabout 0.25 to about 5% (w/v).

Optionally, a fragrance may be added to any of the compositions of theinvention. Fragrances which are useful for the invention include but arenot limited to:

(i) carboxylic acid esters such as octyl acetate, isoamyl acetate,isopropyl acetate and isobutyl acetate;

(ii) fragrant oils such as lavender oil.

The inventive formulations may contain other inert ingredients such asantioxidants, preservatives, or pH stabilizers. These compounds are wellknown in the formulation art. Antioxidants such as vitamin E, alphatocopherol, ascorbic acid, ascorbyl palmitate, citric acid, fumaricacid, malic acid, sodium ascorbate, sodium metabisulfate, sodiummetabisulfite, n-propyl gallate, BHA (butylated hydroxy anisole), BHT(butylated hydroxy toluene), BHA and citric acid, monothioglycerol,tert-butyl hydroquinone (TBHQ), and the like, may be added to thepresent formulation. The antioxidants are generally added to theformulation in amounts of from about 0.01 to about 2.0%, based upontotal weight of the formulation, with about 0.05 to about 1.0% beingespecially preferred.

Preservatives, such as the parabens (methylparaben and/orpropylparaben), are suitably used in the formulation in amounts rangingfrom about 0.01 to about 2.0%, with about 0.05 to about 1.0% beingespecially preferred. Other preservatives include benzalkonium chloride,benzethonium chloride, benzoic acid, benzyl alcohol, bronopol,butylparaben, cetrimide, chlorhexidine, chlorobutanol, chlorocresol,cresol, ethylparaben, imidurea, methylparaben, phenol, phenoxyethanol,phenylethyl alcohol, phenylmercuric acetate, phenylmercuric borate,phenylmercuric nitrate, potassium sorbate, sodium benzoate, sodiumpropionate, sorbic acid, thimerosal, and the like. Preferred ranges forthese compounds include from about 0.01 to about 5%.

Compounds which stabilize the pH of the formulation are alsocontemplated. Again, such compounds are well known to a practitioner inthe art as well as how to use these compounds. Buffering systemsinclude, for example, systems selected from the group consisting ofacetic acid/acetate, malic acid/malate, citric acid/citrate, tartaricacid/tartrate, lactic acid/lactate, phosphoric acid/phosphate,glycine/glycimate, tris, glutamic acid/glutamates and sodium carbonate.

In other embodiments, the topical compositions of the invention may bein the form of a pour-on formulation. Pour-on formulations aredescribed, for example, in U.S. Pat. No. 6,010,710, which isincorporated herein by reference. Some pour-on formulations areadvantageously oily, and generally comprise a diluent or vehicle andalso a solvent (e.g. an organic solvent) for the active ingredient ifthe latter is not soluble in the diluent. Other pour-on formulations maybe in hydrophilic carriers, including in alcohol, glycol or glycol etherbased carriers. Pour-on formulations are typically administered tolivestock animals such as cattle and sheep. Typically, pour-onformulations are administered to the animal as a stripe to an externalsurface of the animal, e.g. a stripe from head to tail of the animal. Inone embodiment, the process comprises applying the solution to livestockanimals before they arrive in the Feed Lot, it being possible for thisapplication to be the final one before the animals are slaughtered.

Typically, the isoxazoline(s) active agents are present in theformulation at a concentration of about 1 to about 25% (w/v). In someembodiments of the invention, the isoxazoline active agents are presentin the formulation as a concentration from about 1 to about 20% (w/v),about 1 to about 10% (w/v), about 5 to about 15% (w/v), or about 5 to10% (w/v). In other embodiments, the isoxazoline active agent(s) arepresent in the compositions at a concentration of about 1 to about 5%(w/v), about 3-6% (w/v) or about 0.5% to about 2.0% (w/v).

The volume of the topical composition applied is not restricted as longas the amount of substance administered is practical and shown to besafe and effective. Typically, the volume applied depends on the sizeand weight of the animal as well as the concentration of active, theextent of infestation by parasites and the type of administration. Forspot-on compositions, the volume applied is typically of the order ofabout 0.1 ml to about 10 ml, about 0.1 ml to about 5 ml, or about 0.1 toabout 1 ml, or, or. In other embodiments, the volume may be about 4 mlto about 7 ml. For larger animals, the volume may be higher including,but not limited to, up to 10 ml, up to 20 ml or higher. In oneembodiment of the volume, the volume is on the order of about 0.5 ml toabout 1 ml or about 0.5 ml to about 2 ml for cats, and on the order ofabout 0.3 to about 3 ml or 4 ml for dogs, depending on the weight of theanimal.

For the pour-on form of the composition, the volume applied can be ofthe order of about 0.3 to about 100 mL. In other embodiments, volumeapplied of the pour-on formulations may be about 1 ml to about 100 ml orabout 1 ml to about 50 ml. In still other embodiments, the volume may beabout 5 ml to about 50 ml or about 10 ml to about 100 ml.

Dosage forms may contain from about 0.5 mg to about 5 g of a combinationof active agents. More typically, the amount of active is present in anamount of from about 1 mg to about 500 mg of an active agent, about 1 mgto about 100 mg or about 1 mg to about 25 mg. In still otherembodiments, the amount of the active agent present in the compositionsis about 10 mg about 50 mg or about 10 mg to about 100 mg. In otherembodiments, the amount of active agent present in the compositions isabout 50 mg to about 200 mg, about 100 mg to about 300 mg, about 100 mgto about 400 mg, about 200 mg to about 500 mg, about 300 mg to about 600mg, about 400 mg to about 800 mg, or about 500 mg to about 1000 mg.

The compositions of the invention are made by mixing the appropriateamount of the active agents, pharmaceutically acceptable carrier ordiluent and optionally a crystallization inhibitor, antioxidant,preservative, film former, etc., to form a composition of the invention.In some embodiments the composition can be obtained by following themethod of making these forms described above by the description ofmaking these forms found in general formulation text known to those inthe art, e.g. Remington—The Science and Practice of Pharmacy (21^(st)Edition) (2005), Goodman & Gilman's The Pharmacological Basis ofTherapeutics (11^(th) Edition) (2005) and Ansel's Pharmaceutical DosageForms and Drug Delivery Systems (8^(th) Edition), edited by Allen etal., Lippincott Williams & Wilkins, (2005).

Methods of Treatment

In another aspect of the invention, a method for preventing or treatinga parasite infestation/infection in an animal is provided, comprisingadministering to the animal a topical composition comprising aneffective amount of at least one isoxazoline active agent together witha pharmaceutically acceptable carrier that is suitable for applicationto the skin of the animal. The compositions or formulations of theinvention have long-lasting efficacy against ectoparasites (e.g. fleasand ticks) and in certain embodiments may also active againstendoparasites that harm animals.

In one embodiment of the invention, methods for the treatment orprevention of a parasitic infestation or infection in a domestic animalare provided, which comprise administering a topical compositioncomprising an effective amount of at least one isoxazoline active agentto the animal. Ectoparasites against which the methods and compositionsof the invention are effective include, but are not limited to, fleas,ticks, mites, mosquitoes, flies and lice. In certain embodiments whereinthe compositions include one or more additional active agents that areactive against internal parasites the compositions and methods of theinvention may also effective against endoparasites including, but notlimited to, cestodes, nematodes, hookworms and roundworms of thedigestive tract of animals and humans.

In one embodiment for treatment against ectoparasites, the ectoparasiteis one or more insect or arachnid including those of the generaCtenocephalides, Rhipicephalus, Dermacentor, Ixodes, Boophilus,Ambylomma, Haemaphysalis, Hyalomma, Sarcoptes, Psoroptes, Otodectes,Chorioptes, Hypoderma, Damalinia, Linognathus, Haematopinus, Solenoptes,Trichodectes, and Felicola.

In another embodiment for the treatment against ectoparasites, theectoparasite is from the genera Ctenocephalides, Rhipicephalus,Dermacentor, Ixodes and/or Boophilus. The ectoparasites treated includebut are not limited to fleas, ticks, mites, mosquitoes, flies, lice,blowfly and combinations thereof. Specific examples include, but are notlimited to, cat and dog fleas (Ctenocephalides felis, Ctenocephalidessp. and the like), ticks (Rhipicephalus sp., Ixodes sp., Dermacentorsp., Amblyoma sp. and the like), and mites (Demodex sp., Sarcoptes sp.,Otodectes sp. and the like), lice (Trichodectes sp., Cheyletiella sp.,Lignonathus sp., and the like), mosquitoes (Aedes sp., Culex sp.,Anopheles sp., and the like) and flies (Hematobia sp. includingHaematobia irritans, Musca sp., Stomoxys sp. including Stomoxyscalcitrans, Dematobia sp., Cochliomyia sp., and the like).

Additional examples of ectoparasites include but are not limited to thetick genus Boophilus, especially those of the species microplus (cattletick), decoloratus and annulatus; myiases such as Dermatobia hominis(known as Berne in Brazil) and Cochliomyia hominivorax (greenbottle);sheep myiases such as Lucilia sericata, Lucilia cuprina (known asblowfly strike in Australia, New Zealand and South Africa). Fliesproper, namely those whose adult constitutes the parasite, such asHaematobia irritans (horn fly) and Stomoxys calcitrans (stable fly);lice such as Linognathus vituli, etc.; and mites such as Sarcoptesscabiei and Psoroptes ovis. The above list is not exhaustive and otherectoparasites are well known in the art to be harmful to animals andhumans. These include, for example migrating dipterous larvae.

In some embodiments of the invention, the composition can also be usedto treat against endoparasites such as those helminths selected from thegroup consisting of Anaplocephala, Ancylostoma, Anecator, Ascaris,Capillaria, Cooperia, Dipylidium, Dirofilaria, Echinococcus, Enterobius,Fasciola, Haemonchus, Oesophagostumum, Ostertagia, Toxocara,Strongyloides, Toxascaris, Trichinella, Trichuris, and Trichostrongylus,among others.

In one embodiment, the invention provides methods for the treatment andprevention of parasitic infections and infestations of animals (eitherwild or domesticated), including livestock and companion animals such ascats, dogs, horses, birds including chickens, sheep, goats, pigs,turkeys and cattle, with the aim of ridding these hosts of parasitescommonly encountered by such animals.

In a preferred embodiment, the invention provides methods andcompositions for the treatment or prevention of parasitic infections andinfestations in companion animals including, but not limited to, catsand dogs. The methods and compositions are particularly effective forpreventing or treating parasitic infestations of cats and dogs withfleas and ticks. In another preferred embodiment, the methods andcompositions of the invention are used for the treatment or preventionof parasitic infections and infestations in cattle or sheep. Whentreating livestock animals such as cattle or sheep, the methods andcompositions are particularly effective against Rhipicephalus(Boophilus) microplus, Haematobia irrilans (horn fly), Stomoxyscalcitrans (stable fly), and sheep myiases such as Lucilia sericata,Lucilia cuprina (known as blowfly strike in Australia, New Zealand andSouth Africa).

The terms “treating” or “treat” or “treatment” are intended to mean theapplication or administration of a composition of the invention to ananimal that has a parasitic infestation for the eradication of theparasite or the reduction of the number of the parasites infesting theanimal undergoing treatment. It is noted that the compositions of theinvention may be used to prevent such a parasitic infestation.

The compositions of the invention are administered in parasiticidallyeffective amounts which are which are suitable to control the parasitein question to the desired extent, as described below. In each aspect ofthe invention, the compounds and compositions of the invention can beapplied against a single pest or combinations thereof.

The compositions of the invention may be administered continuously, fortreatment or prevention of parasitic infections or infestations. In thismanner, the compositions of the invention deliver an effective amount ofthe active compounds to the animal in need thereof to control the targetparasites. By “effective amount” is intended a sufficient amount of acomposition of the invention to eradicate or reduce the number ofparasites infesting the animal. In some embodiments, an effective amountof the active agent achieves at least 70% efficacy against the targetparasite. In other embodiments, an effective amount of the active agentachieves at least 80%, or at least 90% efficacy against the targetpests. Preferably, an effective amount of the active agent will achieveat least 95%, at least 98% or 100% efficacy against the targetparasites.

Generally, a dose of from about 0.001 to about 100 mg per kg of bodyweight given as a single dose or in divided doses for a period of from 1to 5 days will be satisfactory but, of course, there can be instanceswhere higher or lower dosage ranges are indicated, and such are withinthe scope of this invention. It is well within the routine skill of thepractitioner to determine a particular dosing regimen for a specifichost and parasite.

In some embodiments for companion animals, the dose of the isoxazolineactive agent administered from the topical compositions of the inventionis between about 0.1 to about 30 mg per kg of body weight. Moretypically the dose of the isoxazoline active agent administered is about0.5 to about 20 mg/kg or about 0.5 to about 15 mg/kg body weight.Preferably, the dose of the isoxazoline active agent administered isabout 0.5 to about 10 mg/kg, about 0.5 to about 8 mg/kg or about 0.5 toabout 5 mg/kg of body weight.

In certain embodiments for the treatment and prevention of parasiteinfestations and infections in cats, the dose of the isoxazoline activeagent administered will be about 0.5 to about 2 mg/kg of body weight,preferably about 1 mg/kg of bodyweight. In other embodiments for thevery long lasting treatment and protection of cats against parasiticinfestations or infections a dose of about 2 to about 15 mg/kg ofbodyweight or preferably about 5 to about 15 mg/kg of bodyweight will beadministered.

In some embodiments for the treatment and protection of dogs fromparasitic infestations and infections, a dose of about 2 to about 15mg/kg of bodyweight of the isoxazoline active agent will beadministered. In other embodiments, a dose of about 2 to about 8 mg/kgor about 2 to about 5 mg/kg of bodyweight will be administered.

In other embodiments for the treatment of livestock animals such ascattle or sheep, doses of the isoxazoline active agent administered maybe about 1 to about 30 mg/kg of body weight. More typically the dosesadministered will be about 1 to about 20 mg/kg or about 1 to about 15mg/kg. Preferably, a dose of the isoxazoline active agent administeredto livestock animals will be about 1 to about 10 mg/kg of body weight.

Higher amounts may be provided for very prolonged release in or on thebody of the animal. In another treatment embodiment, the amount ofactive agents for birds and other animals which are small in size isgreater than about 0.01 mg/kg, and in another embodiment for thetreatment of small-sized birds and other animals, the amount of isbetween about 0.01 and about 20 mg/kg of weight of animal. Moretypically the dose of the isoxazoline for small-sized animals and birdsis about 0.5 to about 15 mg/kg, about 0.5 to about 10 mg/kg of bodyweight, or about 0.5 mg/kg to about 5 mg/kg of body weight.

In one embodiment of the method of use in dogs or cats, a compositioncomprising an isoxazoline compound has an efficacy against fleas and/orticks of at least about 90.0% or higher for about 1 month, or longer. Inanother embodiment, the compositions of the invention provide anefficacy against fleas and/or ticks of at least 95.0% or higher forabout 30 days, or longer.

In another embodiment, the topical compositions of the invention providean efficacy against fleas and/or ticks in cats and dogs of at leastabout 80% for two months, or longer. In another embodiment, the topicalcompositions provide efficacy against fleas and/or ticks in cats anddogs of about 90% for about two months, or longer. In still anotherembodiment, the compositions provide an efficacy of about 95% for about2 months or longer.

In another embodiment, the composition has an efficacy of at least about80% against fleas and/or ticks for about 3 months, or longer. In stillanother embodiment, the topical compositions of the invention provide anefficacy of at least about 90% against fleas and/or ticks for 3 monthsor longer. In yet another embodiment, the topical compositions of theinvention provide an efficacy of at least about 95% against fleas and/orticks for 3 months or longer. In still another embodiment, the topicalcompositions of the invention provide an efficacy against fleas and/orticks in cats and/or dogs of at least 80% or at least 90% for about 3months to about 6 months or longer.

In one embodiment of the invention, the topical spot-on compositions ofthe invention are administered to the animal over a localized region ofthe animal, e.g. between the two shoulders. In one embodiment of theinvention, the localized region has a surface area of about 10 cm² orlarger. In another embodiment of the invention, the localized region hasa surface area of between about 5 and about 10 cm², or smaller.

In another embodiment of the invention, the pour-on topical compositionsof the invention will be administered in a line along the back of theanimal approximately between the shoulders and the hind quarters.

The solutions according to the invention may be applied using any meansknown per se, e.g. using an applicator gun or a metering flask, pipette,syringes, roll on, droppers, capsules, foil packages, vials, twist tipcontainers, metered-dose aerosols or sprays and other single dose andmulti-dose containers.

In another aspect of the invention, a kit for the treatment orprevention of a parasitic infestation in an animal is provided, whichcomprises at least one isoxazoline active agent together with apharmaceutically acceptable carrier and a dispensing device for topicalapplication of the composition. The dispensing device may be a pipette,syringes, roll on, droppers, capsules, foil packages, vials, twist tipcontainers, metered-dose aerosols or sprays and other single dose andmulti-dose containers, which includes an effective dose of each activeagent in the pharmaceutically acceptable carrier or diluent.

An important aspect of the invention is to provide a multiple-usecontainer comprising a topical composition of the invention, from whichaccurate single dose aliquots of the long lasting topical formulationsmay be administered. The formulation must remain stable with repetitiveexposure to the outside environment, particularly oxygen and water. Thisembodiment may be particularly useful with the very long lastingformulations of the invention that require administration to an animalinfrequently, such as once every 3-6 months, or similar. Some solventssuch as ethers (including DMI, Transcutol® and the like) give rise toperoxides, which then yield ketones and aldehydes that may be furtherdegraded to acids. The presence of acids may contribute to thedegradation of acid hydrolysis-susceptible molecules, includingisoxazoline active agents. Thus, formulation stability is particularlyimportant for the multi-dose container application, where theformulations can be exposed to oxygen and water during multiple roundsof opening and closing. Importantly, it was found that the use ofcertain antioxidants described herein, including BHT and BHA,efficiently inhibit the degradation of the active agent in ethersolvents. For example, a 12% (w/v) solution of Compound A in DMIexhibited no significant change in assay over the course of an elevenweek accelerated stability study at 50° C. in clear glass containers. Inother embodiments, antioxidants such as vitamin E, alpha tocopherol,ascorbic acid, ascorbyl palmitate, citric acid, fumaric acid, malicacid, sodium ascorbate, sodium metabisulfate, sodium metabisulfite,n-propyl gallate, BHA (butylated hydroxy anisole), BHT (butylatedhydroxy toluene), BHA and citric acid, monothioglycerol and the like,may be added to the topical compositions to inhibit the formation ofoxidative species. The antioxidants are generally added to theformulation in amounts of from about 0.01 to about 2.0%, based upontotal weight of the formulation, with about 0.05 to about 1.0% beingespecially preferred.

EXAMPLES

The invention is further described by the following non-limitingexamples which further illustrate the invention, and are not intended,nor should they be interpreted to, limit the scope of the invention.

FORMULATION EXAMPLES

Liquid vehicles suitable for topical isoxazoline-containing formulationsfor control of parasites were investigated. As a non-limiting example,the isoxazoline compound4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamide(Cmpd. A), was investigated for topical delivery to animals, includingcats, dogs and livestock animals such as cattle. Formulations comprisingan isoxazoline compound in combination with one or more additionalactive agents, including (S)-methoprene, pyriproxyfen and nitenpyram,were also prepared and tested.

Formulations were prepared with a variety of liquid carrier vehicles andevaluated for effectiveness to control ectoparasites, particularly fleasand ticks in cats and dogs, and ticks, mites and lice in cattle. Solventsystems comprising either one solvent, including a diester of adicarboxylic acid and/or an ether such as dimethyl isosorbide, or acombination of solvents including a diester of a dicarboxylic acid,specifically diethyl sebacate, and at least a second solvent(s) areencompassed by the invention. In various embodiments, formulationscomprising a single solvent such as DES or DMI or a combination ofsolvents were investigated. Solvents combined with a diester of adicarboxylic acid include, but are not limited to: 1) a propylene glycolester or ether, including PG monocaprylate, PG caprylate, PGmonolaurate, PG dicaprylate/dicaprate, PG caprylic/capric triglycerides(LABRASOL®) or a combination thereof; 2) an ether (e.g. dimethylisosorbide); 3) a second ester (triacetin, lauryl lactate); 4) a fattyacid ester including, but not limited to, isopropyl palmitate,isostearyl lactate, dibutyl adipate, dibutyl sebacate, octyl palmitate,polyethyleneglycol stearate and cetearyl octanoate; 5) a glycol orpolyglycol ether such as Transcutol®, PEG 400 and the like; 6) an oilsuch as mineral oil, diglycerides, triglycerides, jojoba oil, lecithinand castor oil; 7) a long chain aliphatic alcohol such as isostearylalcohol; and 8) mixed esters sucrose and carboxylic acids, includingsucrose acetate isobutyrate (SAIB) and the like.

In other embodiments, the topical compositions of the invention compriseTranscutol®, glycerol formal, triacetin, propylene carbonate, benzylalcohol or DMI.

Non-limiting formulations comprising an isoxazoline compound (Cmpd. A)alone or in combination with the non-limiting additional active agents(S)-methoprene, pyriproxyfen and nitenpyram are provided in below.

Formulation 1—Add diethyleneglycol monoethyl ether (Transcutol®) (50% ofvolume required); Polysorbate 80 and Ethanol are added; the BHA, BHT,povidone 17, and Cmpd. A are then added and mixed until dissolved, andthe mixture is QS with Transcutol®.

Ingredients Function % Cmpd. A Active 3.7, 6.0 w/v (S)-methoprene Active9.0 w/v Polysorbate 80 Surfactant 5.0 w/v Ethanol Spreading agent 10.0v/v Butylated hydroxyanisole Antioxidant 0.02 w/v Butylated hydroxytoluene Antioxidant 0.01 w/v Povidone K-17 Thickener 5.0 w/v Diethyleneglycol monoethyl ether Solvent QSFormulation 2—Add glycerol formal (GF, 50% of required volume), addCmpd. A, dissolve; add DMI; add (s)-methoprene; QS GF.

Ingredients Function % Cmpd. A Active 3.7, 6.0 w/v (S)-methoprene Active9.0 w/v Dimethyl isosorbide Permeation enhancer 25 w/v Glycerol formal(GF) Spreading agent QSFormulation 3—Add diisopropyl adipate (DIPA, 50% of required volume),add Cmpd. A, dissolve; add (s)-methoprene; QS DIPA

Ingredients Function % Cmpd. A Active 3.7, 6.0 w/v (S)-methoprene Active9.0 w/v Diisopropyl adipate (DIPA) Spreading agent QSFormulation 4—Add diethyl sebacate (DES 50% of required volume); add PGmonolaurate; add Cmpd. A, dissolve; add (S)-methoprene; QS DES.

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Propylene glycol monolaurate Permeation enhancer 25.0 v/v DESSpreading agent QSFormulation 5—Add DES (50% of required volume); add PG monocaprylate;add Cmpd. A, dissolve; add (S)-methoprene; QS DES.

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Propylene glycol monocaprylate Permeation enhancer 25.0 v/v (Capryol90) DES Spreading agent QSFormulation 6—Add DIPA (50% of required volume); add Ethyl hexylpelargonate; add Cmpd. A, dissolve; add (S)-methoprene; QS DIPA

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Ethyl hexyl pelargonate Permeation enhancer 25.0 v/v DIPA Spreadingagent QSFormulation 7—Add DIPA (50% of required volume); add diisopropylsebacate; add silicone fluid; add Cmpd. A, dissolve; add (S)-methoprene;QS DIPA

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Diisopropyl sebacate Permeation enhancer 25.0 v/v Silicone fluidSpreading agent 3 v/v DIPA Spreading agent QSFormulation 8—Add Miglyol 840 (50% of required volume); add lauryllactate; add Cmpd. A, dissolve; add (S)-methoprene; QS Miglyol 840

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Lauryl lactate Permeation enhancer 25.0 v/v Miglyol 840 Spreadingagent/ QS permeation enhancerFormulation 9—Add Miglyol 840 (50% of required volume); add triacetin;add Cmpd. A, dissolve: add (S)-methoprene: OS Miglyol 840

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Triacetin Permeation enhancer 25.0 v/v Miglyol 840 Spreading agent/QS permeation enhancerFormulation 10—Add Miglyol 840 (50% of required volume); add Cmpd. A,dissolve; add (S)-methoprene; QS Miglyol 840

Ingredients Function % Cmpd. A Active 6.0 w/v (S)-methoprene Active 9.0w/v Miglyol 840 Spreading agent/ QS permeation enhancerFormulation 11—Add DES (50% of required volume); add Cmpd. A, dissolve;add (S)-methoprene; QS DES

Ingredients Function % Cmpd. A Active 3.0, 4.5, 6.0 w/v (S)-methopreneActive 9.0 w/v DES Spreading agent/ QS permeation enhancerFormulation 12—Add DES (50% of required volume); add Cmpd. A, dissolve;QS DES

Ingredients Function % Cmpd. A Active 6.0 w/v DES Spreading agent/ QSpermeation enhancerFormulation 13—Add DES (50% of required volume); add PG monocaprylate;add Cmpd. A, dissolve; QS DES.

Ingredients Function % Cmpd. A Active  6.0 w/v Propylene glycolmonocaprylate Permeation enhancer 30.0 v/v (Capryol 90) DES Spreadingagent QSFormulation 14—Add DES (30% of required volume); add PGdicaprylate/dicaprate and PG monocaprylate; add Cmpd. A, dissolve; add(S)-methoprene QS DES.

Ingredients Function % Cmpd. A Active 12.0 w/v (S)-methoprene Active9.0% w/v Propylene glycol dicaprylate/ Permeation enhancer 25.0 v/vdicaprate (Capryol PGMC) Propylene glycol monocaprylate Permeationenhancer 25.0 v/v (Capryol 90) DES Spreading agent QSFormulation 15—Add DES (50% of required volume); add, with stirring,lauryl lactate; add Cmpd. A, dissolve; QS DES

Ingredients Function % Cmpd. A Active  6.0 w/v Lauryl Lactate Permeationenhancer 25.0 v/v DES Spreading agent QSFormulation 16—Add DIPA (50% of required volume); add DMI; add Cmpd. A,dissolve; QS DIPA

Ingredients Function % Cmpd. A Active 6.0 w/v w/v Dimethyl isosorbidePermeation enhancer  25 v/v Diisopropyl adipate Spreading agent QS 100%Formulation 17—Add DES (50% of required volume); add DMI; add Cmpd. A,dissolve; QS DES

Ingredients Function % Cmpd. A Active 12.0 w/v w/v Dimethyl isosorbide(DMI) Permeation enhancer   25 v/v DES Spreading agent QS 100%Formulation 18—Add DES (40% of required volume); add DMI; add Cmpd. A,dissolve; QS DES

Ingredients Function % Cmpd. A Active 12.0 w/v w/v DES Spreading agent40% w/v Dimethyl isosorbide (DMI) Permeation enhancer QS 100% v/vFormulation 19—Add DIPA (50% of required volume); add triacetin; addCmpd. A, dissolve; QS DIPA

Ingredients Function % Cmpd. A Active 6.0 w/v Triacetin Permeationenhancer  25 v/v Diisopropyl adipate Spreading agent QS 100%Formulation 20—Add DES (60% of required volume); add mineral oil,medium; add Cmpd. A, dissolve; QS DES

Ingredients Function % Cmpd. A Active 6.0 w/v mineral oil, mediumSubstantivity Agent  25 v/v DES Spreading agent QS 100%Formulation 21—Add DES (60% of required volume); add mineral oil, light;add Cmpd. A, dissolve; QS DES

Ingredients Function % Cmpd. A Active 6.0 w/v mineral oil, lightSubstantivity Agent  25 v/v DES Spreading agent QS 100%Formulation 22—Add DES (60% of required volume); add, with stirring,Transcutol®; add Cmpd. A, mix until dissolved; add SAIB; QS with DES

Ingredients Function % Cmpd. A Active 6.0 w/v Transcutol ® Solvent  20w/v Sucrose acetate isobutyrate (SAM) Controlled release agent   5 w/vDES Spreading agent QS 100%Formulation 23—Add DES (60% of required volume); add, with stirring,Transcutol®; add, with stirring, PEG 400; add Cmpd. A, mix untildissolved; QS with DES

Ingredients Function % Cmpd. A Active 6.0 w/v  Transcutol ® Solvent 20w/v PEG 400 Controlled release agent 10 w/v DES Spreading agent QS 100%Formulation 24—Add Transcutol® (60% of required volume); add, withstirring, PEG 400; add Cmpd. A, mix until dissolved; QS Transcutol®

Ingredients Function % Cmpd. A Active 6.0 w/v PEG 400 Controlled releaseagent   5 w/v Transcutol ® Solvent & Spreading agent QSFormulation 25—Add DES (60% of required volume); add, with stirring,Transcutol®; add, with stirring, PEG 400; add Cmpd. A, mix untildissolved; QS with DES

Ingredients Function % ML Cmpd. A Active 6.0 w/v  Transcutol ® Solvent20 w/v PEG 400 Controlled release agent 10 w/v DES Spreading agent QSFormulation 26—Add DES (60% of required volume); add, with stirring, PEG400; add Cmpd. A, mix until dissolved; QS with DES

Ingredients Function % Cmpd. A Active 6.0 w/v PEG 400 Solvent andControlled  20 w/v release agent DES Spreading agent QSFormulation 27—Add GF (50% of required volume), add Cmpd. A, dissolve;add nitenpyram, dissolve; add DMI; QS GF.

Ingredients Function % Cmpd. A Active 0.8 w/v Nitenpyram Active 1.0 w/vDimethyl isosorbide Permeation enhancer  25 w/v Glycerol formalSpreading agent QSFormulation 28—Add DMI (50% of required volume), add Cmpd. A, dissolve;add nitenpyram, dissolve; add (S)-methoprene and dissolve; QS with DMI.

Ingredients Function % Cmpd. A Active 0.5-2 w/v  Nitenpyram Active  2-8w/v (S)-methoprene Active 7-10 w/v Dimethyl isosorbide Solvent QSFormulation 29—Add DMI (50% of required volume), add Cmpd. A, dissolve;add nitenpyram, dissolve; add pyriproxyfen and dissolve; QS DMI.

Ingredients Function % Cmpd. A Active 0.5-2 w/v   Nitenpyram Active 2-8w/v pyriproxyfen Active 3-6 w/v Dimethyl isosorbide Solvent QSFormulation 30—Add Transcutol® (50% of required volume), add Cmpd. A,dissolve; add nitenpyram, dissolve; add pyriproxyfen and dissolve; QSTranscutol®.

Ingredients Function % Cmpd. A Active 0.5-2 w/v   Nitenpyram Active 2-8w/v pyriproxyfen Active 3-6 w/v Transcutol ® Solvent QSFormulation 31—Add GF (50% of required volume), add Cmpd. A, dissolve;add nitenpyram, dissolve; add pyriproxyfen and dissolve; QS GF.

Ingredients Function % Cmpd. A Active 0.5-2 w/v   Nitenpyram Active 2-8w/v pyriproxyfen Active 3-6 w/v Glycerol formal Solvent QSFormulation 32—Add triacetin (50% of required volume), add Cmpd. A,dissolve; add nitenpyram, dissolve; add pyriproxyfen and dissolve; QStriacetin.

Ingredients Function % Cmpd. A Active 0.5-2 w/v   Nitenpyram Active 2-8w/v pyriproxyfen Active 3-6 w/v triacetin Solvent QSFormulation 33—Add propylene carbonate (50% of required volume), addCmpd. A, dissolve; add nitenpyram, dissolve; add pyriproxyfen anddissolve; QS propylene carbonate.

Ingredients Function % Cmpd. A Active 0.5-2 w/v   Nitenpyram Active 2-8w/v pyriproxyfen Active 3-6 w/v Propylene carbonate Solvent QS

Cmpd. A was found to be stable in at least DES, DIPA, DMI, triacetin, GFand propylene carbonate (at 50° C. in glass bottles).

BIOLOGICAL EFFICACY EXAMPLES Example 1 Efficacy of a Spot-on CompositionComprising a Combination of Cmpd. A and (S)-Methoprene AgainstDermacentor variabilis Ticks and Ctenocephalides Felis Fleas in Dogs

Twenty eight beagle dogs were studied to determine the effectiveness ofa combination of Cmpd. A and (S)-methoprene when administered once as atopical solution against induced infestations of Dermacentor variabilisand Ctenocephalides felis.

Four Treatment Groups containing seven dogs each were formed. Dogs inGroup 1 were untreated (control). Dogs in Groups 2, 3 and 4 were treatedtopically with spot-on compositions comprising 3.7% (w/v) Cmpd. A and 9%(w/v) (S)-methoprene administered to deliver 2.5 mg/kg Cmpd. A and 6mg/kg (S)-methoprene (Group 2: Transcutol with 10% (w/v) ethanol, 5%(w/v) TWEEN 80 and 5% (w/v) polyvinylpyrrolidone; Group 3: DMI andglycerol formal (GF); and Group 4: DIPA). All dogs were treated once onDay 0.

All dogs were infested with approximately 100 C. felis on Days −1, 8,15, 22, 29, 35, 43 and 57, and for all Groups except 5, on Day 71. Alldogs were also infested with approximately 50 D. variabilis on Days −1,7, 14, 21, 28, 34 and 42. Fleas were counted upon removal on Day −6.Both ticks and fleas were counted upon removal on Days 2, 9, 16, 23, 30,36 and 44. Fleas only were counted upon removal for all Treatment Groupson Day 58 and for all Treatment Groups except 5 on Day 72. Flea efficacyis listed in Table 1 and tick efficacy is listed in Table 2 below.

Blood samples were collected from all dogs in the study on Days −6, 0(at 4 h and 12 h), 1, 2, 9, 16, 23, 30, 36, 44, 51, 58, 64, 72, 79 and86. Plasma samples were analyzed for the concentration of Compound Ausing an LC/MS/MS analytical method that was GLP validated for thepurpose.

Percent reduction (also referred as efficacy) against fleas was 100%through and including Day 30 for all treatment groups (see Table 1).Percent reduction against fleas was above 95% through Day 58 for Group3.

The percent reduction against ticks was >94% through and including Day23 (48 hours infestation, see Table 2). Percent reduction was >92% forGroups 6 and 7 on Day 30.

These study data demonstrate that topical formulations comprising Cmpd.A and (5)-methoprene in three different carrier vehicles provided 100%percent reduction for fleas through Day 30 for all treated groups. Tickefficacy was 100% on Days 9 and 16 and two treatment groups (6 and 7)were ≧92% on Day 30.

TABLE 1 Efficacy of a Spot-on Composition Comprising a Combination ofCmpd. A and (S)-methoprene Ctenocephalides felis % Reduction FleasTreatment Day Day Day Day Day Day Day Day Day Group 2 9 16 23 30 36 4458 72 Group 2 100.0 100.0 100.0 100.0 100.0 100.0 86.5 33.2 — %Reduction Group 3 100.0 100.0 100.0 100.0 100.0 100.0 99.6 98.5 89.0 %Reduction Group 4 100.0 100.0 100.0 100.0 100.0 99.8 95.2 89.3 68.9 %Reduction

TABLE 2 Efficacy of a Spot-on Composition Comprising a Combination ofCmpd. A and (S)-methoprene Against Dermacentor variabilis Ticks %Reduction Ticks Treatment Day Day Day Day Day Day Day Group 2 9 16 23 3036 44 Group 2 89.0 100.0 100.0 94.8 65.0 23.3 20.7 % Reduction Group 388.5 100.0 100.0 99.2 94.6 88.3 77.6 % Reduction Group 4 84.3 100.0100.0 97.2 92.0 52.2 57.0 % Reduction

Example 2 Efficacy of Spot-on Formulations Containing Compound A and(S)-Methoprene Against Ctenocephalides felis

Following the initial studies described in Example 1, additional topicalformulations comprising Compound A in combination with an insect growthregulator, (S)-methoprene, in carrier vehicles comprising both aspreading solvent and a permeation solvent were studied. Thus, theefficacy of five different topical formulations comprising Compound Aand (5)-methoprene against the cat flea (Ctenocephalides felis) in dogswas determined using to a protocol similar to that of Example 1.

Seven Treatment Groups with four dogs each were evaluated. Dogs in Group1 were untreated, and served as a control group. Dogs in Groups 2-6 weretreated topically with formulations comprising Cmpd. A and(S)-methoprene in different carrier vehicles administered at 4.0 mg/kgCmpd. A+(S)-methoprene administered at 6 mg/kg (Group 2: Miglyol 840;Group 3: DIPA/25% triacetin; Group 4: DIPA/25% DMI; Group 5 DIPA/25%ethyl hexyl pelargonate; and Group 6: DIPA+25% diisopropyl sebacate+3%silicone fluid). Dogs in Group 7 were treated at a dose level of 7.0mg/kg Compound A+(S)-methoprene at 6 mg/kg with a formulation comprisingDIPA+25% diisopropyl sebacate+3% silicone fluid. The concentrations ofCompound A and (S)-methoprene in formulations of Groups 2-5 were 6.0%(w/v) and 9.0% (w/v), respectively, and the concentration of Compound Aand (S)-methoprene in formulations of Groups 6 and 7 were 10.5% (w/v)and 9% (w/v), respectively.

Dogs were infested with approximately 100 C. felis fleas on Day −1. Dogswere treated with the respective topical formulations on Day 0. Fleaswere removed and counted on Day 2. Infestations with about 100 fleaswere also made on Days 8, 15, 22, 29, 36 and 43. Fleas were combed andcounted 24±3 hours after infestation on Days 9, 16, 23, 30, 37 and 44.

Table 3 below provides the % efficacy for each of the topicalformulations. As demonstrated by the data, each of the formulations washighly efficacious against the cat flea through at least 44 days.

TABLE 3 Efficacy of Spot-on Composition Against Ctenocephalides felisGeometric Mean Flea Count/% Reduction Treatment Day Day Day Day Day DayDay Group 2 9 16 23 30 37 44 Group 2 100.0 100.0 100.0 100.0 100.0 100.098.6 % Reduction Group 3 100.0 99.6 100.0 100.0 100.0 100.0 100.0 %Reduction Group 4 100.0 100.0 100.0 100.0 100.0 100.0 100.0 % ReductionGroup 5 100.0 100.0 100.0 100.0 100.0 100.0 100.0 % Reduction Group 699.6 100.0 100.0 100.0 100.0 100.0 100.0 % Reduction Group 7 100.0 100.0100.0 100.0 100.0 100.0 100.0 % Reduction

Example 3 Efficacy of Spot-on Formulations Containing Compound A and(S)-Methoprene Against Rhipicephalus Sanguineus

In another study, the efficacy against ticks of additional topicalformulations comprising isoxazoline Compound A in combination with(S)-methoprene in further carrier vehicles comprising both a spreadingsolvent and a permeation-enhancing solvent was determined. Thus, sixtopical formulations comprising Compound A and (S)-methoprene weretested for efficacy against Rhipicephalus Sanguineus ticks in beagledogs according to a protocol similar to that of Example 1.

Seven Treatment Groups with four dogs each were evaluated. Dogs in Group1 were untreated, and served as a control group. Dogs in Groups 2-6 weretreated topically with Cmpd. A in different carrier vehiclesadministered at 4.0 mg/kg+(S)-methoprene administered at 6 mg/kg (Group2: Miglyol 840/25% lauryl lactate; Group 3: DIPA/25% triacetin; Group 4:DIPA/25% DMI; Group 5 DIPA/25% Capryol 90/25% Capryol PGMC; and Group 6:DES/25% propylene glycol monolaurate). Dogs in Group 7 were treated at adose level of 7.0 mg/kg Compound A+(S)-methoprene at 6 mg/kg with aformulation comprising DES/25% propylene glycol monolaurate. Theconcentrations of Compound A and (S)-methoprene in the formulations usedwith Groups 2-6 were 6.0% (w/v) and 9.0% (w/v), respectively. Theconcentrations of Compound A and (S)-methoprene in the formulation usedwith Group 7 were 10.5% (w/v) and 9% (w/v), respectively.

All dogs were infested with approximately 50 R. sanguineus on Days −1,7, 14, 21, 28, 35, 42, 49, 56 and 63. Further, Treatment Groups 1, 5, 6and 7 only were infested on Days 70, 77 and 84, and Treatment Groups 1,6 and 7 only on Day 91. Ticks were counted upon removal on Days 2, 9,16, 23, 30, 37, 44, 51, 58 and 65. Tick counts were conducted forTreatment Groups 1, 5, 6 and 7 only on Days 72, 79 and 86 and TreatmentGroups 1, 6 and 7 only on Day 93.

Tables 4A and 4B below presents the efficacy of the spot-on formulationsadministered to Groups 2-7 against R. sanguineus.

TABLE 4A Efficacy Against Rhipicephalus Sanguineus in Dogs % ReductionTicks Treatment Day Day Day Day Day Day Day Group 2 9 16 23 30 37 44Group 2 96.9 100.0 100.0 100.0 100.0 100.0 98.6 % Reduction Group 3 94.5100.0 100.0 100.0 94.5 97.9 97.7 % Reduction Group 4 98.2 100.0 100.0100.0 97.5 94.5 98.6 % Reduction Group 5 98.2 100.0 100.0 98.1 100.097.9 100.0 % Reduction Group 6 100.0 100.0 100.0 100.0 100.0 100.0 100.0% Reduction Group 7 96.9 100.0 100.0 100.0 100.0 100.0 100.0 % Reduction

TABLE 4B Efficacy Against Rhipicephalus Sanguineus in Dogs (continued) %Reduction Ticks Treatment Day Day Day Day Day Day Day Group 51 58 65 7279 86 93 Group 2 100.0 91.3 80.3  ND¹ ND ND ND % Reduction Group 3 95.589.9 65.2 ND ND ND ND % Reduction Group 4 96.4 82.2 77.1 ND ND ND ND %Reduction Group 5 96.7 94.7 87.6 89.1 86.9 67.2 ND % Reduction Group 696.7 100.0 100.0 94.7 90.1 56.0 42.1 % Reduction Group 7 98.3 97.7 95.594.7 100.0 84.5 75.1 % Reduction ¹ND = not done

As Tables 4A and 4B show, Groups 3 and 4 maintained at least a 90%reduction in tick count through Day 51, Groups 2 and 5 through Day 58,and Groups 6 and 7 through Day 79. In particular, Treatment Groups 6 and7 demonstrated superior efficacy for an extended period of time. Thus,formulations comprising a combination of an isoxazoline and an insectgrowth regulator in a carrier vehicle comprising a combination of aspreading solvent and a permeation enhancer were determined to providesurprisingly long lasting efficacy against R. sanguineus.

Example 4 Dose Characterization of Spot-on Formulations of Cmpd. AAgainst Amblyomma americanum Ticks in Dogs

The efficacy of a spot-on composition of the invention comprising anisoxazoline compound (Cmpd. A) in a carrier vehicle comprising eitherDES alone or DES+lauryl lactate (LL), against ticks (Amblyommaamericanum), in dogs was studied. The compositions contained 3.0%, 4.5%,or 6.0% Cmpd. A in either DES alone or DES+lauryl lactate, whichdelivered doses of 4.0 mg/kg, 3.0 mg/kg, and 2 mg/kg, respectively, ofCmpd. A to dogs infested with A. Americanum ticks.

Seven Treatment Groups were evaluated. Treatment Group 1 wasadministered a placebo formulation and served as a control. TreatmentGroups 2, 3 and 4 were administered a topical formulation comprising6.0% (w/v), 4.5% (w/v) and 3.0% (w/v) of Cmpd. A in DES, respectively,corresponding to doses of 4.0 mg/kg, 3.0 mg/kg and 2.0 mg/kg,respectively. Treatment Groups 5, 6 and 7 were administered a topicalformulation comprising 6.0% (w/v), 4.5% (w/v) and 3.0% (w/v) of Cmpd. Ain DES+9% lauryl lactate, respectively, corresponding to doses of 4.0%mg/kg, 3.0 mg/kg and 2.0 mg/kg body weight Cmpd. A, respectively.

All dogs were treated once topically on Day 0 by parting the hair andapplying the solution from a syringe directly onto the skin in a singlespot on the midline of the neck between the base of the skull and theshoulder blades.

All dogs were infested with approximately 50 A. americanum on Days −1,7, 14, 21, 28, 35 and 42. Ticks were counted upon removal on Days 2, 9,16, 23, 30, 37 and 44. The % reduction of ticks for each Group ispresented Table 5 below.

Blood samples were collected from all dogs on Days −5, 0 (at 4 h and 12h), 1, 2, 9, 16, 23, 30, 37 and 44. Plasma samples were analyzed for theconcentration of Compound A using a LC/MS/MS method that was GLPvalidated for the analysis of the compound.

Treatment Groups 5 and 6 (4.0 mg/kg and 3.0 mg/kg Cmpd. A in DES+LL,respectively) maintained at least 90% efficacy through five weeks, andTreatment Group 2 (4.0 mg/kg in DES alone) maintained at least 90%efficacy through Week 3.

TABLE 5 Efficacy Against Amblyomma americanum in Dogs % Reduction TicksTreatment Day Day Day Day Day Day Day Group 2 9 16 23 30 37 44 Group 297.4 100.0 100.0 100.0 82.5 97.9 84.2 % Reduction Group 3 90.0 100.097.6 82.0 70.0 80.4 56.0 % Reduction Group 4 95.4 100.0 100.0 79.5 90.357.1 38.8 % Reduction Group 5 100.0 100.0 100.0 94.3 100.0 89.0 84.8 %Reduction Group 6 98.4 100.0 100.0 93.1 92.1 89.0 53.6 % Reduction Group7 98.4 100.0 100.0 80.6 88.9 74.6 42.4 % Reduction

Example 5 Dose Characterization and Determination of Speed of Kill of aSingle Spot-on Treatment with Formulations of Cmpd. A AgainstCtenocephalides felis Fleas and Rhipicephalus sanguineus Ticks on Dogs

The efficacy of a formulation comprising an isoxazoline compound (Cmpd.A) in a carrier comprising 40% DES/DMI against Ctenocephalides felisfleas and Rhipicephalus sanguineus ticks in Dogs was studied. Asdiscussed above, DES is a solvent with good spreading properties and DMIexhibits good permeation properties. Three treatment groups containingthree dogs each were evaluated. All dogs were treated once topically onDay 0 by parting the hair and applying the solution from a syringedirectly onto the skin in a single spot on the midline of the neckbetween the base of the skull and the shoulder blades.

Treatment Group 1 was a placebo control and received 0.067 mL/kg of bodyweight. Treatment Group 2 was administered a topical spot-on formulationcomprising 6.0% (w/v) Cmpd. A in 40% DES/DMI to deliver a dose of 4.0mg/kg body weight. Treatment Group 3 was administered a topical spot-onformulation comprising 12% (w/v) Cmpd. A in 40% DES/DMI to deliver adose of 4.0 mg/kg body weight.

All dogs were infested with approximately 100 C. felis on Days −1, 7,14, 21, 28, 35 and 42. Fleas were counted upon removal from dogsapproximately 24 hours post infestation on Days 1, 8, 15, 22, 29, 36 and43. The % reduction (efficacy) of each Treatment Group over time islisted in Tables 6A, 6B and 7, respectively.

TABLE 6A Efficacy Against Ctenocephalides felis in Dogs - Day 0 to Day22 Treatment Group Day 1 Day 8 Day 15 Day 22 Group 2 100.0 100.0 100.0100.0 % Reduction Group 3 100.0 100.0 100.0 100.0 % Reduction

TABLE 6B Efficacy Against Ctenocephalides felis in Dogs - Day 28 to Day43 Treatment Group Day 29 Day 36 Day 43 Group 2 100.0 100.0 99.2 %Reduction Group 3 100.0 100.0 100.0 % Reduction

The percent efficacy against ticks is presented in Table 7. BothTreatment Groups demonstrated good efficacy at least through 31 days.

TABLE 7 Efficacy against Rhipicephalus sanguineus Ticks Treatment GroupDay 2 Day 30 Day 31 Day 38 Control Group 2 100.0 91.5 100.0 85.2 %Reduction Group 3 100.0 72.6 100.0 51.3 % Reduction

Example 6 Efficacy of Spot-on Formulations Comprising Compound A atDifferent Doses Against Rhipicephalus sanguineus Ticks in Dogs

A further study was conducted to examine the efficacy of a topicalformulations comprising Compound A in three different formulationscontaining DES against ticks in dogs. Twenty-four beagles were studiedto determine the effectiveness against induced infestations ofRhipicephalus sanguineus of spot-on formulations comprising Cmpd. A indifferent carriers administered at 4.0 mg/kg to dogs.

Treatment Group 1 dogs were treated with a placebo solution. TreatmentGroup 2 was treated with a formulation comprising 6% (w/v) Cmpd. A inDES; Treatment Group 3 were treated with a composition comprising 6%(w/v) Cmpd. A in 40% DES/DMI; and Treatment Group 4 were treated with aformulation comprising 6% (w/v) Cmpd. A in DES with 30% Capryol 90. Alldogs were treated once topically on Day 0. Topical solutions wereapplied by parting the hair and applying the solution from a syringedirectly onto the skin in a single spot on the midline of the neckbetween the base of the skull and the shoulder blades.

All dogs were infested with approximately 50 R. sanguineus on Days −1,7, 14, 21, 28, 35 and 42. Ticks were counted upon removal from dogs onDays 2, 9, 16, 23, 30, 37, and 44. All ticks were counted upon removalat 48 (±3) hours post treatment or infestation.

The percent efficacies of the treated groups compared to the untreatedcontrol group were determined for the 48 hour post-treatment/infestationcounts. Percent efficacy for each counting time 48 hours after treatmentor infestation are listed in Table 8. Treatment Group 3 maintained ≧90%efficacy 48 hours after infestation at every sampling time from Day 9through Day 44. Treatment Group 2 was able to maintain at least 90%efficacy 48 hours after infestation throughout the six weeks of thestudy.

TABLE 8 Efficacy Against Rhipicephalus Sanguineus in Dogs Treatment DayDay Day Day Day Day Day Group 2 9 16 23 30 37 44 Group 2 93.2 100.0100.0 100.0 97.8 95.3 97.5 % Reduction Group 3 72.8 100.0 100.0 100.0100.0 93.5 82.9 % Reduction Group 4 97.2 100.0 100.0 100.0 98.4 96.178.1 % Reduction

Example 7 Efficacy of Spot-on Formulations Comprising IsoxazolineCompound A in Different Carrier Vehicles at 1 mg/kg AgainstCtenocephalides felis Fleas in Cats

The efficacy of several spot-on formulations comprising Cmpd. A dosed at1 mg/kg body weight in different carrier vehicles against fleas in catswas studied. Five cats each were allocated to 6 Treatment Groups. Thesix cats per study group were subjected to weekly infestations followedby 24 h flea counts for 5 to 8 weeks, according to the following Groupallocations: Group 1—untreated control; Group 2—1.0% (w/v) Cmpd. A inDMI; Group 3—1.0% (w/v) Cmpd. A in diethyl sebacate (DES); Group 4—1.0%(w/v) Cmpd. A in 9% lauryl lactate+DES; Group 5—1% (w/v) Cmpd. A in 8%ethyl oleate+DES; and Group 6—1% (w/v) Cmpd. A in a vehicle comprisingTranscutol®+10% (w/v) ethanol+5% polyvinylpyrrolidone+5% TWEEN 80. Catswere infested with approximately 100 C. felis on Day −1 and treated onDay 0 with the corresponding spot-on formulation by application of theformulation directly on the skin in the midline of the neck, between thebase of the skull and the shoulder blades in a single spot using a 1 mLsyringe. Twelve hours after treatment, fleas were removed and counted.The cats were immediately re-infested with approximately 100 fleas.Fleas were removed and counted on Day 1 at approximately 24 hourspost-treatment. Cats were also infested with fleas on Days 7, 21, 38,35, 42 and 49. Fleas were removed and counted approximately 24 hoursafter infestation on Days 8, 22, 29, 36, 43 and 50. The efficacy foreach formulation is presented in Table 9 below.

TABLE 9 Efficacy of Spot-on Formulations Against Ctenocephalides felisFleas in Cats in Different Formulations at a Dose of 1 mg/kg % ReductionDay Treatment 0 Day Day Day Day Day Day Day Group (12 hr) 1 8 22 29 3643 50 Group 2 22.3 28.0 99.3 99.5 98.5 94.2 94.3 87.7 % Reduction Group3 9.6 72.7 99.7 97.4 95.1 79.3 72.2 44.8 % Reduction Group 4 9.2 36.599.7 98.5 98.1 89.3 92.7 79.2 % Reduction Group 5 65.9 77.2 98.4 96.995.0 85.5 79.7 64.0 % Reduction Group 6 17.7 75.6 100.0 99.3 97.5 93.893.9 79.6 % Reduction

As Table 9 demonstrates, all of the spot-on formulations comprisingCmpd. A were highly effective against fleas for at least 29 days. Theformulation administered to Group 2 longer lasting efficacy above 90%until at least Day 43 and maintained efficacy above 85% until Day 50.The formulation of Group 5 (8% ethyl oleate in DES) exhibitedsignificant efficacy after 12 hours.

Example 8 Efficacy of Spot-on Formulations Comprising IsoxazolineCompound A in Different Carrier Vehicles at 1 mg/kg AgainstCtenocephalides felis Fleas in Cats Protected from Grooming

In another study, the efficacy of four spot-on formulations comprisingCmpd. A dosed at 1 mg/kg body weight in different carrier vehiclesagainst fleas in cats was studied. Five cats each were allocated to fiveTreatment Groups: Group 1—Untreated; Group 2—0.833% (w/v) Cmpd. A indimethylsulfoxide (DMSO); Group 3—0.833% (w/v) Cmpd. A in DMI; Group4—0.833% (w/v) Cmpd. A in Transcutol®; and Group 5—0.833% (w/v) Cmpd. Ain DES. Each cat in the study was fitted with a protective neck collaron Day −1 prior to treatment to prevent the animals from orallyingesting the topically applied formulation while grooming. Cats wereinfested with approximately 100 C. felis on Day −1 and treated on Day 0with the corresponding spot-on formulation by application of theformulation directly on the skin in the midline of the neck, between thebase of the skull and the shoulder blades in a single spot using a 1 mLsyringe. Infestations with approximately 100 C. felis were conductedweekly on Days 7, 14, 21, 28 and 35. Fleas were removed and countedapproximately 24±3 hours following treatment on Day 1 and then on Days8, 15, 22, 29 and 36. The efficacy for each formulation is presented inTable 10 below.

TABLE 10 Efficacy of Spot-on Formulations Against Ctenocephalides felisFleas in Cats % Reduction Treatment Day Day Day Day Day Day Day Group 12 8 15 22 29 36 Group 2 43.16 60.54 98.48 95.91 97.90 90.10 74.49 %Reduction Group 3 37.90 88.97 99.62 99.32 98.80 92.66 79.54 % ReductionGroup 4 76.32 83.12 98.95 99.01 96.19 95.41 86.61 % Reduction Group 554.40 82.77 98.82 99.26 99.82 92.43 88.11 % Reduction

Example 9 Long Lasting Efficacy of Spot-on Composition AgainstCtenocephalides felis Fleas in Cats

The efficacy of spot-on compositions comprising Cmpd. A in DMI atdifferent doses against Ctenocephalides felis fleas in cats was studied.Four treatment groups were formed with five cats per treatment group:Group 1—untreated control; Group 2—Compound A at 5.0% (w/v) in DMI todeliver a dose of 5 mg/kg; Group 3—Compound A at a concentration of10.0% (w/v) in DMI to deliver a dose of 10 mg/kg; and Group 4—Compound Aat a concentration of 15.0% (w/v) in DMI to deliver a dose of 15 mg/kg.Treatment was administered once on Day 0. The cats were each infestedwith approximately 100 C. felis fleas at each time point evaluated.

Cats in all treatment groups were infested on Days −1, 0 (approx. 12 hfollowing treatment), 7, 28, 49, 70, 91, 105, 119 and 133. Cats werealso infested on Days 126 and 140 (Treatment Groups 1 and 2); Days 147,154, 155, 161, 168 and 175 (Treatment Groups 1, 3 and 4); Days 182, 189and 197 (Treatment Groups 1 and 4). After each infestation, fleas wereremoved and counted approximately 48 hours (±3 hours) for most timepoints.

The results of the study are shown in Tables 11A, 11B and 11C below andin FIG. 1. The study demonstrated surprising long lasting efficacy ofthe spot-on formulations. The results indicate that formulationscomprising Cmpd. A at different concentrations were efficacious comparedto Group 1 (untreated control) for extended periods of time. For exampleGroup 2 demonstrated 90% efficacy up to Day 121; Group 3 showed 90%efficacy up to Day 163 and Group 4 exhibited 90% efficacy up to Day 191.This extremely long lasting protection above 90% from one topicalapplication is unpredictable and remarkable.

TABLE 11A Efficacy of Against Ctenocephalides felis Fleas in Cats %Reduction Fleas Day Treatment 0 Day Day Day Day Day Day Group (12 hr) 29 30 51 72 93 Group 2 61.1 100.0 100.0 100.0 100.0 100.0 100.0 %Reduction Group 3 95.4 100.0 100.0 100.0 100.0 100.0 100.0 % ReductionGroup 4 85.3 100.0 100.0 100.0 100.0 100.0 100.0 % Reduction

TABLE 11B Efficacy of Against Ctenocephalides felis Fleas in Cats(continued) % Reduction Fleas Treatment Day Day Day Day Day Day DayGroup 107 121 128 135 142 149 155 Group 2 100.0 92.3 89.1 88.3 80.0 NDND % Reduction Group 3 100.0 100.0 ND 99.8 ND 99.5 50.0 % ReductionGroup 4 100.0 100.0 ND 100.0 ND 100.0 78.0 % Reduction

TABLE 11C Mean Flea Count/% Reduction (continued): % Reduction FleasTreatment Day Day Day Day Day Day Day Group 157 163 170 177 184 191 199Group 2 ND ND ND ND ND ND ND % Reduction Group 3 98.1 94.5 87.8 70.8 NDND ND % Reduction Group 4 100.0 100.0 96.2 94.8 95.7 90.6 79.2 %Reduction

Example 10 Efficacy of Spot-on Formulations Against Ixodes ricinus Ticksin Cats

The efficacy of spot-on formulations comprising Cmpd. A were studiedagainst induced infestations of Ixodes ricinus ticks in cats. Threetreatment groups with six cats per group were randomly allocated: Group1—Control, untreated; Group 2—Cmpd. A (2.5% w/v in DMI) at 0.1 ml/kgbody weight (2.5 mg/kg); and Group 3—Cmpd. A (5.0% w/v in DMI) at 0.1ml/kg body weight (5 mg/kg). Treatment was administered once on Day 0and efficacy was assessed based on 48-hour tick (I. ricinus) countsfollowing weekly experimental challenge from Day 7 on. As shown inTables 12A and 12B below, Cmpd. A (2.5% w/v in DMI) at 2.5 mg/kg bodyweight administered once topically completely prevented the infestationof I. ricinus until Day 56 and offered >90% prevention until at leastDay 77. In fact, the topical spot-on formulation offered substantialprotection against I. ricinus ticks until the last day of assessment—Day93. Due to limitations on tick availability 5 mg/kg was tested only upto Day 44 with 100% efficacy. The excellent long-lasting efficacy of theformulation of the invention against I. ricinus ticks in cats is verysurprising and unexpected.

TABLE 12A Efficacy Against Ixodes ricinus in Cats % Reduction TicksTreatment Day Day Day Day Day Day Group 2 9 23 30 37 44 Group 2 23.71100.00 99.60 100.00 99.58 100.00 % Reduction Group 3 70.27 100.00 100.00100.00 100.00 100.00 % Reduction

TABLE 12B Efficacy Against Ixodes ricinus in Cats (continued) %Reduction Ticks Treatment Day Day Day Day Day Day Day Group 51 58 65 7279 86 93 Group 2 100.00 100.00 99.02 99.21 95.54 84.92 76.65 % ReductionGroup 3 ND¹ ND ND ND ND ND ND % Reduction ¹ND = not done

Example 11 Efficacy of Spot-on Formulation Containing a Combination ofCompound A, Pyriproxyfen and Nitenpyram Against Ctenocephalides felisFleas in Cats

The efficacy of three spot-on compositions comprising a combination ofCompound A, pyriproxyfen and nitenpyram against Ctenocephalides felisfleas in cats was studied and compared with an untreated control andwith a spot-on composition comprising nitenpyram alone. Cats wereallocated into five Treatment Groups with 5 cats per group: Group 1—catswere untreated (control); Group 2—cats were treated spot-on solutioncontaining 0.83% (w/v) Compound A, 2.08% (w/v) nitenpyram, and 4.17%(w/v) pyriproxyfen in Transcutol® to deliver doses of 1.0 mg/kg CompoundA, 2.5 mg/kg nitenpyram and 5.0 mg/kg pyriproxyfen; Group 3—cats weretreated a spot-on solution containing 0.83% (w/v) Compound A, 4.17%(w/v) nitenpyram, and 4.17% (w/v) pyriproxyfen in Transcutol® to deliverdoses of 1.0 mg/kg Compound A, 5.0 mg/kg nitenpyram and 5.0 mg/kgpyriproxyfen; Group 4—cats were treated with a spot-on compositioncontaining 0.83% (w/v) Compound A, 8.33% (w/v) nitenpyram and 4.17%(w/v) pyriproxyfen in Transcutol® to deliver doses of 1.0 mg/kg CompoundA, 10.0 mg/kg nitenpyram and 5.0 mg/kg pyriproxyfen; Group 5—cats weretreated with a spot-on composition containing 2.08% (w/v) nitenpyramalone in Transcutol® to deliver a dose of 5.0 mg/kg body weight.

Treatment was administered once on Day 0. The cats were each infestedwith approximately 100 C. felis fleas at day −1, on Day 0 approximately12 hours post treatment and then on Days 1 (approx. 24 hours posttreatment), 2, 7, 14, 21, 28 and 35. After each infestation, fleas wereremoved and counted approximately 12 hours (±3) on Day 0, and then onDays 1, 2, 8, 15, 22, 29 and 36 (24±3 hours after infestation).

The results of the study are shown in Table 13 below. The studydemonstrated that a spot-on composition comprising a combination of anisoxazoline compound (Compound A), a neonicotinoid (nitenpyram) and aninsect growth regulator (pyriproxyfen) exhibits extremely fast actingand long-lasting efficacy.

TABLE 13 Efficacy of Spot-on Formulation Comprising Three Active AgentsAgainst Ctenocephalides felis Fleas in Cats % Reduction Day Day Day DayDay Day Treatment 0 1 2 8 15 22 Group (12 h) (24 h) (24 h) (24 h) (24 h)(24 h) Group 2 99.17 100.00 100.00 100.00 100.00 98.76 % Reduction Group3 99.59 99.22 99.78 100.00 99.51 97.71 % Reduction Group 4 97.69 100.00100.00 100.00 100.00 98.08 % Reduction Group 5 99.44 99.79 100.00 100.0096.76 93.63 % Reduction

Example 12 Efficacy of Spot-on Compositions Comprising Compound AAgainst Otodectes Cynotis (Ear Mites) in Cats

The efficacy of two spot-on compositions comprising Compound A at dosesof 5 mg/kg and 10 mg/kg against Otodectes cynotis in cats was evaluatedcompared to an untreated control. Eighteen healthy cats were groupedinto three study groups consisting of six cats per group. Cats in thetreatment groups were infested with Otodectes cynotis obtained fromnaturally infested donor cats prior to acclimation on Day −7. Group 1was an untreated control group. Cats in Groups 2 and 3 were treated onceon Day 0 with a spot-on composition comprising Compound A at twodifferent concentrations and doses by application of the formulationdirectly on the skin in the midline of the neck between the base of theskull and the shoulder blades with a 1 mL disposable syringe. Cats inGroup 2 were treated with a spot-on composition containing 5.0% (w/v)Compound A in a carrier containing 40% (v/v) diethyl sebacate (DES) indimethylisosorbide (DMI) at a dose of 5 mg/kg body weight; and cats inGroup 3 were treated with a spot-on composition containing 10.0% (w/v)Compound A in a carrier containing 40% (v/v) DES in DMI at a dose of 10mg/kg body weight. Assessment of the ear mite infestation by otoscopicexamination was performed on all cats on Days −7, 3, 7 and 14. Visiblelive ear mites (adult or immature) were counted and debris/cerumen levelwas estimated for both ear ducts. A quantitative assessment of ear mitesby ear duct flushing, mite collection and live mite count was performedon Day 14. Relative to the untreated control, Group 2 reduced theinfestation of ear mites by 99.0% (only one mite found) and Group 3reduced the infestation of ear mites by 100.0% (no live mites found inany cat).

Example 13 Efficacious Plasma Concentration for Topical Compositions

Plasma concentrations of Compound A from dogs in the studies of Examples1 and 4 were determined according to the description in Example 1, andthe plasma concentration versus % efficacy against A. americanum and D.variabilis were fit to a Sigmoidal Emax model. The EC₉₀ (concentrationrequired to achieve 90% efficacy) against A. americanum and D.variabilis ticks were determined to be 92 ng/mL and 70 ng/mL,respectively. Using a similar approach, the EC₉₀ for R. sanguineus ticksfrom a separate study was found to be 69 ng/mL. For comparison, the EC₉₀values from an oral dosage form against A. americanum, D. variabilis andR. sanguineus ticks was found to be 158 ng/mL, 110 ng/mL and 101 ng/mL,respectively. Since Compound A is systemically active, the lowerconcentration of the compound in the plasma required to achieve 90%efficacy from the topical compositions of the invention is surprisingand unexpected.

Example 14 Efficacy of Pour-on Formulation Against Haematobia irritans(Horn Fly) in Cattle

The efficacy of a pour-on formulation of the invention comprisingisoxazoline Compound A was tested and compared with an untreatedcontrol. Two healthy, female Angus crossbread cattle of one year of ageweighing between 224 to 330 kg were used in each study group. Cattle inGroup 1 were untreated (control) and cattle in Group 2 were treated witha pour-on formulation comprising Compound A at a concentration of 10%(w/v) in DES at a dose of 1 ml/10 kg once on Day 0. The formulation wasapplied by measuring the required amount of the solution into a markeddisposable syringe and applying the material evenly along the mid-lineof the back of each animal from the withers to the tail head. Eachanimal was infested with approximately 200 horn flies released into eachof the animal rooms on Day 1, approximately 24 hours post treatment.Approximately 200 horn flies were released again on Days 7, 14, 21, 28and 36. Horn fly counts were performed at 5 hours and 24 hours aftereach infestation. Tables 14A and 14B below show the efficacy of thepour-on formulation of the invention.

TABLE 14A Efficacy of Pour-on Formulation Against Horn Fly % ReductionDay Day Day Day Day Day Treatment 1 2 7 8 14 15 Group¹ (5 h) (24 h) (5h) (24 h) (5 h) (24 h) Group 2 81.2 99.6 84.2 99.7 89.5 99.2 % Reduction

TABLE 14B Efficacy of Pour-on Formulation Against Horn Fly (Continued) %Reduction Day Day Day Day Day Day Treatment 21 22 28 29 35 36 Group¹ (5h) (24 h) (5 h) (24 h) (5 h) (24 h) Group 2 67.6 97.4 11.7 90.4 42.690.4 % Reduction

As the tables 14A and 14B show, significant efficacy against horn flieswas observed after only 5 hours post infestation. Efficacy of at least90% was observed 24 hours after infestation through the end of the study(day 36).

Example 15 Efficacy of Pour-on Formulation Against Rhipicephalus(Boophilus) Microplus Ticks

The efficacy of two pour-on formulations of the invention comprisingCompound A at doses of 2.5 mg/kg and 10 mg/kg were tested againstinfestations of Rhipicephalus (Boophilus) microplus ticks compared withan untreated control. Five healthy head of cattle of 6 to 15 months ofage weighing between 100 to 200 kg were used in each study group. Cattlein Group 1 were untreated (control). Cattle in Group 2 were treated onDay 0 with a pour-on formulation comprising Compound A at aconcentration of 2.5% (w/v) in DES at a dose of 2.5 mg/kg; and cattle inGroup 3 were treated on Day 0 with a pour-on formulation comprisingCompound A at a concentration of 10% (w/v) in DES at a dose of 10 mg/kg.Several weeks before treatment, cattle are infested three times a weekwith approximately 2500 Rhipicephalus (Boophilus) microplus larvae toestablish ongoing infestations. Cattle in Groups 2 and 3 were treatedwith the respective compositions on Day 0 by measuring the requiredamount of the solution into a marked disposable syringe and applying thematerial evenly along the mid-line of the back of each animal from thewithers to the tail head.

Each animal was challenged by infestation with approximately 5000 R.microplus larvae on Days 7 and 21 and every 14 days thereafter. Ticksdropping from each animal in the previous 24 hours were collected dailyand counted from Day 1 until the end of the study. Since the life cycleof the ticks from the point of infestation with larvae until engorgedticks fall off is approximately 21 days (average), the assessment ofefficacy for the challenges on Days 7 and 21 and every 14 daysthereafter, was done for a range of 7 or 8 days starting approximately21 days after the challenge. The assessment of efficacy at the beginningof the study was done from day 1 until Day 21.

In addition, the ticks collected were weighed as a group to measure theimpact of the treatment on the weight gain of the ticks compared to thecontrol to assess the vitality and reproductive capability of thetreated ticks. Tables 15A and 15B below shows the total tick count %efficacy of the two pour-on formulations against R. microplus through139 days post treatment compared with an untreated control group. Tables16A and 16B show the % efficacy of the two pour-on formulations based onthe weight of the ticks collected. FIGS. 2 and 3 shows plots of the %efficacy of the two formulations based on total tick counts and totalweight, respectively. As evidenced from the tables and the figures, thepour-on formulations of the invention at both 2.5 mg/kg and 10 mg/kgprovide excellent efficacy against Rhipicephalus (Boophilus) microplusticks for an extended period of time. The pour-on compositions exhibitedtick count efficacy above 90% for at least day 139 after administrationof the composition. Furthermore, as shown in Tables 16A and 16B, the twopour-on compositions were extremely effective against ticks based on theweight of the ticks collected. This data shows that the compositionswere highly effective at inhibiting the reproductive capability of theticks for an extended duration of time. The extremely long lastingefficacy above 90% for pour-on composition against Rhipicephalus(Boophilus) microplus ticks is remarkable compared with pour-onformulations known in the art.

TABLE 15A Tick Count Efficacy Against Rhipicephalus (Boophilus)microplus Average % Efficacy (Tick Count) Treatment Day Day Day Day DayDay Day Group 1-21 28-34 41-48 55-62 69-76 83-90 97-104 Challenge Day 721 35 49 63 77 Group 2 58.8 75.6 77.0 91.2 88.3 90.7 79.8 % EfficacyGroup 3 78.1 92.0 98.0 97.8 99.3 98.9 92.4 % Efficacy

TABLE 15B Tick Count Efficacy Against Rhipicephalus (Boophilus)microplus Average % Efficacy (Tick Count) Day Day Day Day TreatmentGroup 111-118 132-139 146-153 160-167 Challenge Day 91 112 126 140 Group2 79.0 86.2 30.3 74.0 % Efficacy Group 3 96.6 92.4 72.4 85.8 % Efficacy

TABLE 16A Tick Weight Efficacy Against Rhipicephalus (Boophilus)microplus Average % Efficacy (Tick Weight) Treatment Day Day Day Day DayDay Day Group 1-21 28-34 41-48 55-62 69-76 83-90 97-104 Challenge Day 721 35 49 63 77 Group 2 69.1 81.8 72.9 87.7 84.8 87.4 76.0 % EfficacyGroup 3 85.4 95.2 98.3 96.6 99.2 98.6 90.2 % Efficacy

TABLE 16B Tick Weight Efficacy Against Rhipicephalus (Boophilus)microplus Average % Efficacy (Tick Weight) Day Day Day Day TreatmentGroup 111-118 132-139 146-153 160-167 Challenge Day 91 112 126 140 Group2 74.0 83.2 20.6 63.4 % Efficacy Group 3 96.0 92.4 61.4 76.3 % Efficacy

Example 16 Efficacy of Pour-on Formulation Against Linognathus vituli(Sucking Lice) in Cattle

The efficacy of two pour-on formulations of the invention comprisingisoxazoline Compound A at doses of 2.5 mg/kg and 10 mg/kg were testedagainst natural and induced infestations with Linognathus vituli(sucking lice) in cattle compared with an untreated control. Fourhealthy head of cattle weighing between 100 to 300 kg were used in eachstudy group. Cattle in Group 1 were untreated (control). Cattle in Group2 were treated on Day 0 with a pour-on formulation comprising Compound Aat a concentration of 2.5% (w/v) in DES at a dose of 2.5 mg/kg; andcattle in Group 3 were treated on Day 0 with a pour-on formulationcomprising Compound A at a concentration of 10% (w/v) in DES at a doseof 10 mg/kg. The formulation was applied by measuring the requiredamount of the solution into a marked disposable syringe and applying thematerial evenly along the mid-line of the back of each animal from thewithers to the tail head.

Live lice (adults plus nymphs) were counted on days 2, 7, 14, 21, 28,35, 42, 49 and 56 by counting lice on six selected sites approximately 5cm×15 cm on the body surface of the animal by direct examination. In theabsence of lice on the selected sites, a thorough body search wasconducted. The total louse counts per animal were determined bysummation of the live louse numbers at each site per animal. Tables 17Aand 17B below show the efficacy of the two pour-on formulations againstLinognathus vituli over 56 days. As the tables show, both pour-onformulations were efficacious through at least day 56 of the study with100% efficacy observed starting day 7. Efficacy on day 2 of the studywas greater than 90% in each of the study groups. The long lastingefficacy against Linognathus vituli from one topical treatment isunexpected and surprising.

TABLE 17A Efficacy of Pour-on Formulation Against Linognathus vituli %Reduction Treatment Group¹ Day 2 Day 7 Day 14 Day 21 Day 28 Group 2 92100 100 100 100 % Reduction Group 3 98 100 100 100 100 % Reduction

TABLE 17B Efficacy of Pour-on Formulation Against Linognathus vituli(continued) % Reduction Treatment Group Day 35 Day 42 Day 49 Day 56Group 2 92 100 100 100 % Reduction Group 3 98 100 100 100 % Reduction

Example 17 Efficacy of Pour-on Formulation Against Sarcoptes ScabieiVar. Bovis (Mange Mites) in Cattle

The efficacy of two pour-on formulations of the invention comprisingisoxazoline Compound A at doses of 2.5 mg/kg and 10 mg/kg were testedagainst natural and induced infestations with Sarcoptes scabiei var.bovis (mange mites) in cattle compared with an untreated control. Fourhealthy head of cattle weighing between 100 to 300 kg were used in eachstudy group. Cattle in Group 1 were untreated (control). Cattle in Group2 were treated on Day 0 with a pour-on formulation comprising Compound Aat a concentration of 2.5% (w/v) in DES at a dose of 2.5 mg/kg; andcattle in Group 3 were treated on Day 0 with a pour-on formulationcomprising Compound A at a concentration of 10% (w/v) in DES at a doseof 10 mg/kg. The formulation was applied by measuring the requiredamount of the solution into a marked disposable syringe and applying thematerial evenly along the mid-line of the back of each animal from thewithers to the tail head.

Live (motile) Sarcoptes scabiei var. bovis (mange mites) were counted ondays 7, 14, 20, 27, 34, 41, 48 and 55 in scrapings collected from theedges of active lesions or, if lesions regressed during the study, fromthe area where active lesions were at the commencement of the study.Scrapings were made from six sites with an area of at least 3 cm×3 cm insize on each animal. Tables 18A and 18B below show the efficacy of thetwo pour-on formulations against Sarcoptes scabiei var. bovis over 56days. As the data shows, both pour-on formulations were efficaciousthrough at least day 56 of the study with efficacy of higher than 95%starting on day 7. The efficacy of the 10% (w/v) formulation exhibitedan efficacy of 100% from day 14 through day 55, while the efficacy ofthe lower concentration pour-on formulation (Group 2) showed 100%starting from day 27 through the end of the study. The long lastingefficacy of the pour-on formulations of the invention against Sarcoptesscabiei var. bovis from one topical treatment is unexpected andsurprising.

TABLE 18A Efficacy of Pour-on Formulation Against Sarcoptes scabiei var.bovis % Reduction Treatment Group Day 7 Day 14 Day 20 Day 27 Group 296.7 98.2 99.6 100 % Reduction Group 2 96.8 100 100 100 % Reduction

TABLE 18B Efficacy of Pour-on Formulation Against Sarcoptes scabiei var.bovis (continued) % Reduction Treatment Group Day 34 Day 41 Day 48 Day55 Group 2 100 100 100 100 % Reduction Group 2 100 100 100 100 %Reduction

As the non-limiting examples above demonstrate, the compositions of theinvention comprising at least one isoxazoline active agent show superiorlong lasting efficacy against ectoparasites in a mammal (e.g. dogs, catsand cattle).

The invention is further described by the following numbered paragraphs:1. A topical veterinary composition for treating or preventing aparasitic infection or infestation in an animal comprising:

a) at least one isoxazoline active agent of Formula (I):

wherein:

A¹, A², A³, A⁴, A⁵ and A⁶ are independently selected from the groupconsisting of CR³ and N, provided that at most 3 of A¹, A², A³, A⁴, A⁵and A⁶ are N;

B¹, B² and B³ are independently selected from the group consisting ofCR² and N;

W is O or S;

R¹ is C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₄-C₇alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, each optionally substitutedwith one or more substituents independently selected from R⁶;

each R² is independently H, halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₁-C₆alkoxy, C₁-C₆ haloalkoxy, C₁-C₆ alkylthio, C₁-C₆ haloalkylthio, C₁-C₆alkylsulfinyl, C₁-C₆ haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆haloalkylsulfonyl, C₁-C₆ alkylamino, C₂-C₆ dialkylamino, C₂-C₄alkoxycarbonyl, —CN or —NO₂;

each R³ is independently H, halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₃-C₆cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, —CN or —NO₂;

R⁴ is H, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₄-C₇ alkylcycloalkyl, C₄-C₇ cycloalkylalkyl, C₂-C₇ alkylcarbonyl orC₂-C₇ alkoxycarbonyl;

R⁵ is H, OR¹⁰, NR¹¹R¹² or Q¹; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇cycloalkylalkyl, each optionally substituted with one or moresubstituents independently selected from R⁷; or

R⁴ and R⁵ are taken together with the nitrogen to which they areattached to form a ring containing 2 to 6 atoms of carbon and optionallyone additional atom selected from the group consisting of N, S and O,said ring optionally substituted with 1 to 4 substituents independentlyselected from the group consisting of C₁-C₂ alkyl, halogen, —CN, —NO₂and C₁-C₂ alkoxy;

each R⁶ is independently halogen, C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆alkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆ alkylsulfonyl, —CN or —NO₂;

each R⁷ is independently halogen; C₁-C₆ alkyl, C₃-C₆ cycloalkyl, C₁-C₆alkoxy, C₁-C₆ alkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆alkylamino, C₂-C₈ dialkylamino, C₃-C₆ cycloalkylamino, C₂-C₇alkylcarbonyl, C₂-C₇ alkoxycarbonyl, C₂-C₇ alkylaminocarbonyl, C₃-C₉dialkylaminocarbonyl, C₂-C₇ haloalkylcarbonyl, C₂-C₇ haloalkoxycarbonyl,C₂-C₇ haloalkylaminocarbonyl, C₃-C₉ dihaloalkylaminocarbonyl, hydroxy,—NH₂, —CN or —NO₂; or Q²;

each R⁸ is independently halogen, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, C₂-C₄ alkoxycarbonyl, —CN or —NO₂;

each R⁹ is independently halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₃-C₆cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, —CN, —NO₂, phenyl or pyridinyl;

R¹⁰ is H; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, eachoptionally substituted with one of more halogen;

R¹¹ is H, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₄-C₇ alkylcycloalkyl, C₄-C₇ cycloalkylalkyl, C₂-C₇ alkylcarbonyl orC₂-C₇ alkoxycarbonyl;

R¹² is H; Q³; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, eachoptionally substituted with one or more substituents independentlyselected from R⁷; or

R¹¹ and R¹² are taken together with the nitrogen to which they areattached to form a ring containing 2 to 6 atoms of carbon and optionallyone additional atom selected from the group consisting of N, S and O,said ring optionally substituted with 1 to 4 substituents independentlyselected from the group consisting of C₁-C₂ alkyl, halogen, —CN, —NO₂and C₁-C₂ alkoxy;

Q¹ is a phenyl ring, a 5- or 6-membered heterocyclic ring, or an 8-, 9-or 10-membered fused bicyclic ring system optionally containing one tothree heteroatoms selected from up to 1 O, up to 1 S and up to 3 N, eachring or ring system optionally substituted with one or more substituentsindependently selected from R⁸;

each Q² is independently a phenyl ring or a 5- or 6-memberedheterocyclic ring, each ring optionally substituted with one or moresubstituents independently selected from R⁹;

Q³ is a phenyl ring or a 5- or 6-membered heterocyclic ring, each ringoptionally substituted with one or more substituents independentlyselected from R⁹; and

n is 0, 1 or 2; and

b) a pharmaceutically acceptable carrier that is suitable forapplication to the skin of an animal; and wherein the carrier does notcomprise glycofurol and is not a binary mixture of propylene glycol andglycerol formal.

2. The topical veterinary composition of paragraph 1, wherein in theisoxazoline active agent of Formula (I):

-   -   W is O;    -   R⁴ is H or C₁-C₆ alkyl;    -   R⁵ is —CH₂C(O)NHCH₂CF₃;    -   each of A², A³, A⁴, A⁵ and A⁶ is CH;    -   is C₁-C₆ alkyl each optionally substituted with one or more        substituents independently selected from R⁶;    -   R⁶ is halogen or C₁-C₆ alkyl; and    -   B¹, B², and B³ are independently CH, C-halogen, C—C₁-C₆ alkyl,        C—C₁-C₆ haloalkyl, or C—C₁-C₆ alkoxy.        3. The topical veterinary composition of paragraph 1, wherein in        the isoxazoline active agent of Formula (I):

W is O;

R¹ is CF₃;

B² is CH;

B¹ is chloro;

B³ is CF₃;

each of A¹, A², A³, A⁴, A⁵ and A⁶ is CH;

R⁴ is H; and

R⁵ is —CH₂C(O)NHCH₂CF₃.

4. The topical veterinary composition of paragraph 1, wherein thepharmaceutically acceptable carrier comprises a diester of adicarboxylic acid, a glycol ester, a glycol ether, a fatty acid ester, apolyethylene glycol, or polyethylene glycol ester, an oil, an alcohol, aglycerol ester, a glycerol ether, propylene glycol, ethylene glycol, aglycol carbonate, dimethyl isosorbide, N-methylpyrrolidone, or a mixturethereof.5. The topical veterinary composition of paragraph 4, wherein thediester of a dicarboxylic acid is a diester of a C₆-C₁₆ dicarboxylicacid.6. The topical veterinary composition of paragraph 5, wherein thediester of a C₆-C₁₆ dicarboxylic acid is diethyl sebacate or diisopropyladipate.7. The topical veterinary composition of paragraph 4, wherein thepharmaceutically acceptable carrier comprises mixture of a diester of adicarboxylic acid and a propylene glycol ester, a fatty acid ester, apolyethylene glycol ester, a polyethylene glycol, an oil, a C₆-C₂₀long-chain aliphatic alcohol, a C₁-C₈ alcohol, glycol ether, or acombination thereof.8. The topical veterinary composition of paragraph 4, wherein thepharmaceutically acceptable carrier comprises a mixture of a diester ofa dicarboxylic acid and further comprises a mixed ester of sucrose andacetic and isobutyric acid, a low melting wax, a hard fat or a blockco-polymer of ethylene oxide and propylene oxide, or a combinationthereof.9. The topical veterinary composition of paragraph 4, wherein thepharmaceutically acceptable carrier comprises dimethyl isosorbide,glycerol formal, propylene carbonate, triacetin, diethyleneglycolmonoethyl ether, polyethylene glycol 400 or benzyl alcohol, or a mixturethereof.10. The topical veterinary composition of any one of paragraph 1 to 9,wherein the composition further comprises at least a second activeagent.11. The topical veterinary composition of paragraph 10, wherein the atleast second active agent is an insect growth regulator, a neonicotinoidor an avermectin or milbemycin.12. The topical veterinary composition of paragraph 11, wherein theisoxazoline active agent is4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalanecarboxamideand the neonicotinoid is nitenpyram.13. The topical veterinary composition of paragraph 11, wherein the atleast second active agent is an insect growth regulator.14. The topical veterinary composition of paragraph 13, wherein theinsect growth regulator is (S)-methoprene, pyriproxyfen, hydroprene,cyromazine, fluazuron, lufenuron, or novaluron.15. The topical veterinary composition of paragraph 11, wherein theavermectin or milbemycin is eprinomectin, ivermectin, selamectin,milbemectin, milbemycin D, milbemycin oxime, or moxidectin16. The topical veterinary composition of paragraph 10, wherein the atleast second active agent is an anthelmintic active agent selected fromthiabendazole, oxibendazole, mebendazole, fenbendazole, oxfendazole,albendazole, triclabendazole, febantel, levamisole, pyrantel, morantel,praziquantel, closantel, clorsulon, an amino acetonitrile active agent,or an aryloazol-2-yl cyanoethylamino active agent.17. The topical veterinary composition of any one of paragraph 1 to 16,wherein the composition is a spot-on composition.18. The topical veterinary composition of any one of paragraph 1 to 16,wherein the composition is a pour-on composition.19. A method for the treatment or prevention of a parasitic infestationor infection in an animal comprising administering to the animal aneffective amount of the topical veterinary composition of any ofparagraph 1 to 18.20. The method of paragraph 19, wherein the isoxazoline is4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4,5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalenecarboxamide.21. Use of an isoxazoline of formula (I) in paragraph 1 in thepreparation of a topical veterinary composition for the treatment orprotection of an animal against parasites.

Having thus described in detail various embodiments of the presentinvention, it is to be understood that the invention defined by theabove paragraphs is not to be limited to particular details set forth inthe above description as many apparent variations thereof are possiblewithout departing from the spirit or scope of the present invention.

1-21. (canceled)
 22. A topical veterinary composition for treating orpreventing a parasitic infection or infestation in an animal comprising:a) at least one isoxazoline active agent of Formula (I):

wherein: A¹, A², A³, A⁴, A⁵ and A⁶ are independently selected from thegroup consisting of CR³ and N, provided that at most 3 of A¹, A², A³,A⁴, A⁵ and A⁶ are N; B¹, B² and B³ are independently selected from thegroup consisting of CR² and N; W is O or S; R¹ is C₁-C₆ alkyl, C₂-C₆alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇cycloalkylalkyl, each optionally substituted with one or moresubstituents independently selected from R⁶; each R² is independently H,halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy,C₁-C₆ alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, C₂-C₄ alkoxycarbonyl, —CN or —NO₂; eachR³ is independently H, halogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, C₃-C₆cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆ alkoxy, C₁-C₆ haloalkoxy, C₁-C₆alkylthio, C₁-C₆ haloalkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ haloalkylsulfonyl, C₁-C₆alkylamino, C₂-C₆ dialkylamino, —CN or —NO₂; R⁴ is H, C₁-C₆ alkyl, C₂-C₆alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl, C₄-C₇ alkylcycloalkyl, C₄-C₇cycloalkylalkyl, C₂-C₇ alkylcarbonyl or C₂-C₇ alkoxycarbonyl; R⁵ is H,OR¹⁰, NR¹¹R¹² or Q¹; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇ cycloalkylalkyl, eachoptionally substituted with one or more substituents independentlyselected from R⁷; or R⁴ and R⁵ are taken together with the nitrogen towhich they are attached to form a ring containing 2 to 6 atoms of carbonand optionally one additional atom selected from the group consisting ofN, S and O, said ring optionally substituted with 1 to 4 substituentsindependently selected from the group consisting of C₁-C₂ alkyl,halogen, —CN, —NO₂ and C₁-C₂ alkoxy; each R⁶ is independently halogen,C₁-C₆ alkyl, C₁-C₆ alkoxy, C₁-C₆ alkylthio, C₁-C₆ alkylsulfinyl, C₁-C₆alkylsulfonyl, —CN or —NO₂; each R⁷ is independently halogen; C₁-C₆alkyl, C₃-C₆ cycloalkyl, C₁-C₆ alkoxy, C₁-C₆ alkylthio, C₁-C₆alkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆ alkylamino, C₂-C₈dialkylamino, C₃-C₆ cycloalkylamino, C₂-C₇ alkylcarbonyl, C₂-C₇alkoxycarbonyl, C₂-C₇ alkylaminocarbonyl, C₃-C₉ dialkylaminocarbonyl,C₂-C₇ haloalkylcarbonyl, C₂-C₇ haloalkoxycarbonyl, C₂-C₇haloalkylaminocarbonyl, C₃-C₉ dihaloalkylaminocarbonyl, hydroxy, —NH₂,—CN or —NO₂; or Q²; each R⁸ is independently halogen, C₁-C₆ alkoxy,C₁-C₆ haloalkoxy, C₁-C₆ alkylthio, C₁-C₆ haloalkylthio, C₁-C₆alkylsulfinyl, C₁-C₆ haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆haloalkylsulfonyl, C₁-C₆ alkylamino, C₂-C₆ dialkylamino, C₂-C₄alkoxycarbonyl, —CN or —NO₂; each R⁹ is independently halogen, C₁-C₆alkyl, C₁-C₆ haloalkyl, C₃-C₆ cycloalkyl, C₃-C₆ halocycloalkyl, C₁-C₆alkoxy, C₁-C₆ haloalkoxy, C₁-C₆ alkylthio, C₁-C₆ haloalkylthio, C₁-C₆alkylsulfinyl, C₁-C₆ haloalkylsulfinyl, C₁-C₆ alkylsulfonyl, C₁-C₆haloalkylsulfonyl, C₁-C₆ alkylamino, C₂-C₆ dialkylamino, —CN, —NO₂,phenyl or pyridinyl; R¹⁰ is H; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇cycloalkylalkyl, each optionally substituted with one of more halogen;R¹¹ is H, C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆ alkynyl, C₃-C₆ cycloalkyl,C₄-C₇ alkylcycloalkyl, C₄-C₇ cycloalkylalkyl, C₂-C₇ alkylcarbonyl orC₂-C₇ alkoxycarbonyl; R¹² is H; Q³; or C₁-C₆ alkyl, C₂-C₆ alkenyl, C₂-C₆alkynyl, C₃-C₆ cycloalkyl, C₄-C₇ alkylcycloalkyl or C₄-C₇cycloalkylalkyl, each optionally substituted with one or moresubstituents independently selected from R⁷; or R¹¹ and R¹² are takentogether with the nitrogen to which they are attached to form a ringcontaining 2 to 6 atoms of carbon and optionally one additional atomselected from the group consisting of N, S and O, said ring optionallysubstituted with 1 to 4 substituents independently selected from thegroup consisting of C₁-C₂ alkyl, halogen, —CN, —NO₂ and C₁-C₂ alkoxy; Q¹is a phenyl ring, a 5- or 6-membered heterocyclic ring, or an 8-, 9- or10-membered fused bicyclic ring system optionally containing one tothree heteroatoms selected from up to 1 O, up to 1 S and up to 3 N, eachring or ring system optionally substituted with one or more substituentsindependently selected from R⁸; each Q² is independently a phenyl ringor a 5- or 6-membered heterocyclic ring, each ring optionallysubstituted with one or more substituents independently selected fromR⁹; Q³ is a phenyl ring or a 5- or 6-membered heterocyclic ring, eachring optionally substituted with one or more substituents independentlyselected from R⁹; and n is 0, 1 or 2; and b) a pharmaceuticallyacceptable carrier that is suitable for the application to the skin ofan animal; and wherein the carrier comprises dimethyl isosorbide. 23.The topical veterinary composition of claim 1, wherein: W is O; R⁴ is Hor C₁-C₆ alkyl; R⁵ is —CH₂C(O)NHCH₂CF₃; each of A¹, A², A³, A⁴, A⁵ andA⁶ is CH; R¹ is C₁-C₆ alkyl each optionally substituted with one or moresubstituents independently selected from R⁶; R⁶ is halogen or C₁-C₆alkyl; and B¹, B², and B³ are independently CH, C-halogen, C—C₁-C₆alkyl, C—C₁-C₆ haloalkyl, or C—C₁-C₆ alkoxy.
 24. The topical veterinarycomposition of claim 1, wherein: W is O; R¹ is CF₃; B² is CH; B¹ isC-chloro; B³ is C—CF₃; each of A¹, A², A³, A⁴, A⁵ and A⁶ is CH; R⁴ is H;and R⁵ is —CH₂C(O)NHCH₂CF₃.
 25. The topical veterinary composition ofclaim 1, wherein the pharmaceutically acceptable carrier furthercomprises a glycol ether, a fatty acid ester, an alcohol, a glycerolester, a glycerol ether, propylene glycol, ethylene glycol, a glycolcarbonate or N-methylpyrrolidone, or a mixture thereof.
 26. The topicalveterinary composition of claim 25, wherein the pharmaceuticallyacceptable carrier comprises a glycol ether.
 27. The topical veterinarycomposition of claim 26, wherein the glycol ether is diethylene glycolmonoethyl ether, butyl diglycol, dipropylene glycol n-butyl ether,ethylene glycol monoethyl ether, ethylene glycol monomethyl ether,dipropylene glycol monomethyl ether, propylene glycol monomethyl etheror propylene glycol monoethyl ether.
 28. The topical veterinarycomposition of claim 25, wherein the pharmaceutically acceptable carriercomprises a glycerol ether.
 29. The topical veterinary composition ofclaim 28, wherein the glycerol ether is glycerol formal.
 30. The topicalveterinary composition of claim 22, wherein the pharmaceuticallyacceptable carrier further comprises a mixed ester of sucrose and aceticand isobutyric acid, a low melting wax, a hard fat or a block co-polymerof ethylene oxide and propylene oxide, or a combination thereof.
 31. Thetopical veterinary composition of claim 25, wherein the pharmaceuticallyacceptable carrier comprises a combination of dimethyl isosorbide andglycerol formal, propylene carbonate, triacetin, diethyleneglycolmonoethyl ether or benzyl alcohol, or a mixture thereof.
 32. The topicalveterinary composition of claim 31, wherein the pharmaceuticallyacceptable carrier comprises a combination of dimethyl isosorbide andglycerol formal.
 33. The topical veterinary composition of claim 22,wherein the composition further comprises at least a second activeagent.
 34. The topical veterinary composition of claim 33, wherein theat least second active agent is an insect growth regulator, aneonicotinoid, a depsipeptide, praziquantel, an avermectin or amilbemycin, or a combination thereof.
 35. The topical veterinarycomposition of claim 34, wherein the at least second active agent is aninsect growth regulator.
 36. The topical veterinary composition of claim35, wherein the insect growth regulator is (S)-methoprene, pyriproxyfen,hydroprene, cyromazine, fluazuron, lufenuron, or novaluron.
 37. Thetopical veterinary composition of claim 34, wherein the compositioncomprises an avermectin, and wherein the avermectin is eprinomectin,ivermectin, abamectin, doramectin, emamectin or selamectin.
 38. Thetopical veterinary composition of claim 34, wherein the compositioncomprises a milbemycin, and wherein the milbemycin is moxidectin ormilbemycin oxime.
 39. The topical veterinary composition of claim 34,wherein the at least second active agent is praziquantel.
 40. Thetopical veterinary composition of claim 34, wherein wherein the at leastsecond active agent is a combination of an avermectin and praziquantel;and wherein in the isoxazoline active agent of formula (I): W is O; R¹is CF₃; B² is CH; B¹ is C-chloro; B³ is C—CF₃; each of A¹, A², A³, A⁴,A⁵ and A⁶ is CH; R⁴ is H; and R⁵ is —CH₂C(O)NHCH₂CF₃.
 41. The topicalveterinary composition of claim 40, wherein the avermectin iseprinomectin.
 42. The topical veterinary composition of claim 22,wherein the composition is a spot-on composition.
 43. The topicalveterinary composition of claim 22, wherein the composition is a pour-oncomposition.
 44. The topical veterinary composition of claim 24, whereinthe composition comprises about 1 to about 25% (w/v) of the compound offormula (I).
 45. The topical veterinary composition of claim 24, whereinthe composition comprises about 1 to about 5% (w/v) of the compound offormula (I).
 46. The topical veterinary composition of claim 24, whereinthe composition comprises about 5 to about 15% (w/v) of the compound offormula (I).
 47. The topical veterinary composition of claim 41, whereinthe composition comprises about 1 to about 25% (w/v) of the compound offormula (I).
 48. The topical veterinary composition of claim 41, whereinthe composition comprises about 1 to about 5% (w/v) of the compound offormula (I).
 49. A method for the treatment or prevention of a parasiticinfestation or infection in an animal comprising administering to theanimal an effective amount of the topical veterinary composition ofclaim
 22. 50. The method of claim 49, wherein the in the isoxazoline offormula (I): W is O; R¹ is CF₃; B² is CH; B¹ is C-chloro; B³ is C—CF₃;each of A¹, A², A³, A⁴, A⁵ and A⁶ is CH; R⁴ is H; and R⁵ is—CH₂C(O)NHCH₂CF₃.
 51. The method of claim 49 or 50, wherein the animalis a cat.
 52. The method of claim 50, wherein the composition comprisesat least a second active agent, and wherein the second active agent isan insect growth regulator, a neonicotinoid, a depsipeptide,praziquantel, an avermectin or a milbemycin, or a combination thereof.53. The method of claim 52, wherein the composition comprises anavermectin, and wherein the avermectin is eprinomectin, ivermectin,abamectin, doramectin, emamectin or selamectin.
 54. The method of claim52, wherein the composition comprises a milbemycin, and wherein themilbemycin is moxidectin or milbemycin oxime.
 55. The method of claim52, wherein the at least second active agent is praziquantel.
 56. Themethod of claim 52, wherein the at least second active agent is acombination of an avermectin and praziquantel.
 57. The method of claim56, wherein the avermectin is eprinomectin.
 58. The method of claim 52,wherein the composition is a spot-on composition.
 59. The method ofclaim 52, wherein the composition is a pour-on composition.